SMITHSOXIA4N CONTRIBUTIONS TO BOTAKY NUhlBER 19 

The Genus Thrinax 

(Falmae: Coryphoideae) 

Robert W. Read 

SMITHSONIXN INSTITUTION PRESS 

City of IYashington 

1975 
ABSTRACT 

Read, Robert W. The Genus Thrinax (Palmae: Coryphoideae). Smithsonian 

ContriOutions to Botany, number 19, 98 pages, frontispiece, 57 figures, 1975.-The 

history, distribution, ecology, morphology, cytology, anatomy, and taxonolny of 

the four species of Thrinax are presented. The objective is to demonstrate that 

quantitative characters, formerly believed to be important in distinguishing 

species, merely represent random selections from clinal patterns and are therefore 

of little value in distinguishing taxa. Certain characters described for the first 

time-leaf sheath, blade, color and puberulence of the inflorescence-have proved 

to be of great taxonomic value. Particular attention is given to tlie variability 

of Thrinax parvifiora Sw. over a wide range of climatic conditions and to its 

unusual phenotypic behavior, in special situations, in the Cockpit Country and 

on the slopes of Mt. Diablo in Jamaica. The haploid chromosome number (determined at pollen-tube mitosis) of all four species is 18. Little difference in size 

or morphology of the chromosomes exists among these taxa. Anatomically all 

four species can be distinguished by comparison of leaf segment sections. 

The taxonomic portion is a thorough revision of the genus. It includes literature references, synonymy, complete descriptions, and specimens examined. 

Thrinax parvipora Sw. and T. excelsa Lodd. ex Griseb. are endemic to Jamaica 

while T. mdinta Lodd. ex J. A. & J. H. Schult. occurs in the littoral of the Greater 

Antilles (except Puerto Rico), tlie Bahamas, Florida, and Mexico. Th1-inax 

morrisii H. Wendl. occurs on most of the islands from Anegada (east of the 

Virgin Islands) to the islands off the coast of British Honduras, and Florida, but 

not in Jamaica. 

OFFICIAL PUBLICATION DATE is handstamped in a limited number of initial copies and is recorded 

in the Institutions annual report, Smithsonian Year. SI PRESS NUMHFR 5125. SI.RIES COWR nmm: 

Leaf clearing from the Katsura tree Cercidiphyllurn jnponicunz Siebold and Znccarini. 

Library of Congress Cataloging in Publication Data 

Read, Robert L$’., 1931- 

The genus Thrinax (Palmae: Coryphoideae) 

(Smithsonian contributions to botany, no. 19) 

1. Thrinax , I. Title. 11. Series: Smithsonian Institution. Smithsonian contributions to botany, 

QKl .S274’i no. 19 [QK495.P17] 581’.08s [584‘5] 74-6489 no. 19. 

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20402 Price $2.40 (paper coler) 
Contents 

Page 

Introduction 1 

Acknowledgments .......................................... 2 

History of the Genus .............................................. 3 

Distribution and Ecology .......................................... 7 

Thyinax radiata ............................................... 7 

Thrinax excelsa ............................................... 11 

Thyinax mowisii ............................................ 13 

.................................................... 

Thrinax parviflora ............................................ 13 

Morphology ............................................. .... 17 

Selection of Samples for Measurement .......................... 17 

Caudex ...................................................... 19 

Leaf ....................................................... 19 

Inflorescence ................................................. 28 

Germination of Seeds ..................................... 38 

Pollen ..................................................... 38 

Anatomy ........................................................ 39 

Anatomical Key to the Species of Thyinax Using Laminar Characters ... 41 

Material and Methods .... ........................ 41 

Lamina ..................................................... 41 

Material and Methods ................................. 44 

48 

52 

59 

Cytology ....................................................... 44 

Phytomorphosis and Zoomorphosis in Thrinax parviflora ............... 

Breeding System .................................................. 48 

Variation of Thrinax pai-viflo~.n., .................................... 

Transect from Portland Ridge to Hollymount, Jamaica ............. 

Donkey Trail Transect ..................................... 63 

Thyinax Swartz ............................................... 66 

Key to the Species of Thl-inax .................................. 

Typification of Thrinax ParuifEora ............................ 

Diagnostic Key to the Subspecies of Thrinax parvipora ............ 

68 

1 Thyinax paruiflora 69 

70 

74 

75 

76 

. ........................................... 

Thrinax parvifiora Swartz subsp . parvipom ..................... 

Th?~inax pat-uiflora Swartz pziberula, new subspecies ................ 

2 . Thrinax radiata ........................................... 77 

3 . Thrinax excelsa 84 

4 . Thrinax monisii ............................................. 88 

Appendix 11: Nomina Incerta et Dubia ......................... 95 

......................................... 

Appendix I: Binomials Published in the Genus Thrinax .............. 94 

Literature Cited ...................... , ......................... 96 

... 

111 

The Genus Thrinax 

(Palmae: Coryphoideae) 

Robert W. Read 

Introduction 

Thrinax is a genus of true palmate-leaved palms 

in the subfamily Coryphoideae. The genus occurs 

only on the islands of the northern Caribbean and 

the nearby continental coastal areas bordering on 

the Gulf Stream. Its nearest allies are Hemitlzrinax 

and Coccothrinax, which share the same general 

range of distribution. 

The genus Thrinax may be recognized by the 

unarmed split leaf-petioles, flowers with a single 

whorl of perianth, and nonruininate seeds which 

have the center partially or completely intruded by 

the testa. Stamen number varies from 5 to 15 

(rarely more) and the abaxial surface of the leaf 

may or may not be white or silvery. Fully mature 

fruits are always white or ivory colored. 

At the beginning of this study five species of 

Thrinax were attributed to Jamaica with an additional seven or eight distributed throughout the 

Caribbean region apart from Jamaica. With the 

exception of a few quantitative Characters of dubious value, no convincing differences could be 

found between Beccari’s T. parviflora, T. tessellata, 

and T. harrisiana. This was also true concerning 

T. mowisii of FVendland, T. ponceana and T. psaeceps of Cook, T. drtidei and T. puncttilata of 

Beccari, and T. miclocarpa ol‘ Sargent. Similarly, 

Bailey’s T. parvifloi.a and T. excelsa were separated 

in a key based solely on the size of the fruit and 

leaf segments. During the present study it has been 

found that, with the exception of Beccari’s T. parviflora (in part), none of the names in common use 

Robert Tt’. Read, Department of Botany, Smithsonia?~ Itistitution, Washington, D.C. 20560. 

1 

have been applied correctly, and all of the names 

of the species not occurring in Jamaica are to be 

relegated to synonymy or to subspecific status of 

the least commonly used specific epithet. The reasons for the previous confusion are inadequate 

herbarium material and a lack of understanding 

of the variability of Thrinax species in natural 

populations. 

My interest in Thrinax developed as a result 

of an attempt to understand the palms of southern 

Florida, and the necessity of clearing up nomenclatural problems of the plants used in my cytological studies. After several trips to the islands of the 

Caribbean, and to Jamaica in particular, it was 

soon obvious that the same taxon known in Florida 

as T. parviflora was known under a different specific epithet on each of the various islands. In 

Jamaica, the type locality of T. parzri%ora Sw., the 

Florida taxon was known as T. excelsa and the 

epithet T. parviflora was applied to an entirely 

distinct but very poorly understood local taxon. It 

was clear that a study of the Jamaican taxa of 

Thrinax was essential before an understanding of 

the taxa elsewhere was possible. 

Before revisionary work in palms could be accomplished at the species level, it was essential to 

understand the range and type of variation possible within each taxon and to have some understanding of the effects of environment on the 

variation. It was also important to determine the 

kinds of characters (key characters) which unquestionably distinguish taxa and which remain recognizable regardless of environment. Far too often 

descriptions of palms drawn from incomplete and 

and inadequate collections have been relied upon 
2 

for identification. The situation clearly stated by 

Joseph D. Hooker and Thomas Tlionison (1855) 

has been found true today in the study ol‘ palms. 

They wrote that “the niore specimens we examined, 

and especially if taken from different indivicluals, 

the greater the difficulty in framing diagnosis. . . . 

iVe are firmly convinced that no species can be 

properly defined, until it has been examined in all 

the variations induced by those differences in climate, locality, and soil.’’ It seems superfluous to 

restate these well-knoTvn facts, but this basic information lias yet to be acquired in most tropical 

families, particularly those with large cumbersome 

plants such as the Palmae. 

No amount of statistical analysis, numerical 

taxonomy, or classical taxonomy for that matter, 

Trill solve the problems of species definition when 

based on inadequate collections, incomplete herbarium specimens, and insufficient knowledge of ecological tolerances. A study of tlie scope undertaken 

here is too laborious and time-consuming to be 

applied Fvithin the foreseeable future to niore than 

a fraction of the palm species described. Proof of 

conclusions regarding genetic differences is not 

possible without transplant experiments; but the 

obstacles to long-term experiments ivitli such slolvly 

developing plants as paliiis preclude this approach. 

Proper study of palms lias until recently also 

been hampered because ol their size, complexity, 

general unuielcliness, and inaccessibility in tropical 

regions. In addition, portions of the plants \vliicli 

did not conl‘orni to the limits set by the standard 

herbarium sheet or “pigeonholes” were often tlisregarded by collectors. The opportunity ~va5 taken 

during this study to make intensive observations of 

Tkiirznx in tlie field and to analyze antl present the 

data in a comparative Tvay for taxonomic purposes. 

This has led to detailed examination of the development and mature condition 01 all organs Tvliose 

nature could in any Tray assist the accurate antl 

complete definition of the genus Tlzrinnx antl its 

species in Jamaica. 

The result is a statement of tlie natural variability of Tlz~iiznx against the background ol the pliysical factors 01 tlie environment, leading to a 

complete taxonomic revision of the genus. 

.CK~.O~~LEL)G~lT~Ts.-The basis of the present 

monograph is a thesis for the P1i.D. degree. The 

author rrishes to express his sincere appreciation to 

5hlITHSO\I4\ COATRIBLTIOXS TO ZOTANY 

Dr. C. Dennis Adams of the Botany Department 

of tlie University of the ’1Vest Indies for his valuable advice, guidance, and patience during the 

investigations and preparation of tlie original manuscript; and to Dr. Harold E. Moore of the Liberty 

Hytle Bailey Hortorium, Cornell University, who 

has contributed immeasurably by providing information, suggestions, and reading tlie manuscript. 

Very special thanks are extended to the Botany 

Department of tlie University of the West Indies, 

and to George R. Proctor of the Institute of 

Jamaica, for providing transportation, assistance, 

and facilities during the studies in Jamaica; and 

especially to Dr. and Nrs. Ivor Cornman for their 

contribution to the success of many trips into the 

“bush.” 

Sincere appreciation is also extended to tlie directors and staff of numerous herbaria and libraries 

for photographs, loan or use of herbarium material 

and freely given information, assistance, and encouragement; especially Dr. William Dress of Corriel1 University; Dr. George Bunting, formerly at 

Cornell University; Dr. Richard A. Howard, Director of tlie Arnold Arboretum; Drs. Lyman B. Smith 

and Velva Rudd of the National hluseuni of Natural History, Smithsonian Institution; Dr. Howard 

Irwin of the New York Botanical Garden; Mr. 

George W. Rosner, Richter Library, University of 

Miami, Florida; Dr. T.V. T. Stearn of the British 

hIuseuiii (Natural History); hlr. ’Iy. hlilne-Redhead 

of Kew Royal Botanic Gardens; Dr. C. E. B. Bonner of the Conservatoire et Jardiii botaniques, 

Geneve; Prof. Tycho Norlindh and Barron Sparre 

of the Naturhistoriska Riksniuseum, Stockholm; 

Drs. H. AIerxmuller and A%. Schreiber of the Botanische Staatssammlung, hlunich; antl to hlr. 

Harold Loomis, former director of the United 

States Plant Introduction Station in Xliami, Florida, 

lor his early encouragement and knowledge of the 

palms at the time I was starting to get interested 

in the family. 

Additional research ~vas made possible for me as 

a National Research Council Visiting Research 

Associate in the Department of Botany, Smithsonian Institution, later as a Research Associate of 

tlie Department, and now as an Associate Curator 

in the same Institution. This has made it possible 

to change “A Study of the Genus Thiinnx in Jamaica” into a monograph of the genus as a whole. 
AUXIBER 19 3 

History of the Genus 

Although Linnaeus did not include any palms 

of the Caribbean islands in his Species Planlarum, 

their existence had been recorded by various authors during the century prior to 1753. In tact Sir 

Hans Sloane (1696) described ten true palms in his 

Catalogiis Plantarurn, of which one has been determined to be a member of the genus Thrinax. It is 

important to understand that while Sloane ~vas 

writing specifically of palms he observed in Jamaica, 

he also attempted to identify them with descriptions already in the literature. This association of 

earlier accounts Tvith the Jamaican palms n’as often 

incorrect; therefore in order to understand the 

application of Sloane’s descriptions, it is essential 

to ignore these misleading synonymies. Nor did 

that practice end with Sloane for it has continued 

to plague the study of palms to the present. 

The palm to be discussed most fully in the 

present paper appeared for the first time in the 

literature as the last true palm mentioned by 

Sloane (1696: 178, 179). Sloane unfortunately associated the Jamaican “thatch” with Ray’s “4. Palnin 

Biasiliensis p~zinife~n” (1688: 1368 ) because of the 

similarity of the leaf form. Ray’s palm, liolvever, is 

Brazilian antl has been determined to belong to the 

genus Copemicia (Noore, 1963). Since no Cofiernick has been found in Jamaica, the plicate-leaved 

palm growing “In sylvis saxosis k collibus sterilioribus Jamaicae Insulae ubiyue reperitur” (Sloane 

1696: 179) can only be one of those presently knoivn 

as Thi.innx or Coccotkiinox. In 1525, Sloane again 

cited “Palma Bmsiliensis” as the “thatch” (1). 121) 

of Jamaica and again the sole indication of its 

identity, in the text, is that, “This grows on all tlie 

Honey-comb Rocks of this island” (p. 122). Sloane’s 

pl. 213: fig. 2 of tlie same lvork, holvever, unquestionably illustrates a Thrinax-like palm leaf. The 

lack of teeth on the petiole, the nonacuminate 

hastula, and the irregular fusion of the segments, 

it‘ this xvas intended to be diagnostic, clearly intlicate that this illustration depicts the plant no~v 

determined to be Thrinax pawij7oi.a Sw. 

The first complete account of a palm readily 

identifiable as Th~inax parvij7orn Sw. in the literature appeared in Patrick Browne’s Civil ai7d Xntziral Histoyy of Jamaica, published in 1756. The 

Latin diagnosis of “Coryphn I. Palniacen” 1 is accurate, but the association of Kay’s Brazilian palm 

again apparently contributed to Grisebacli’s (1 864) 

belief that a Copemicia was to be found in Jamaica. 

In 1‘784, Olof Swartz left Sweden at the age of 

24 and spent tlie next two years traveling through 

the West Indies and Jamaica. Follolving his trip 

through the Caribbean, Swartz \vent to England to 

study the Hans Sloane Jamaican collection and the 

herbarium of Sir Joseph Banks at the British Museum. Within two years of his return to Siveden he 

published (1788) the first of his major works 011 

LVest Indian plants, Souti Genera et Species Plantal-unz sell Prodronzzis. In the Prodromus, as it is 

known, appeared the first published description of 

the palm Thi.inax parviflo~a. A diagnosis of the 

genus appeared on page 4, number 29, and tlie 

single species was described on page 57. 

It is possible that Swartz went to Jamaica with 

some foreknorvledge of the palm lie later described 

as Tlzrinax pawifiora. Although he gave no indication in the P?.odromiis of the source of the name 

or its meaning, he attempted to rectify his debt to 

Linnaeus the younger by inserting a note ol‘ acknowledgment in his Flo1.a (1797). That the younger Linnaeus was preparing to publish the binomial, 

before his death in 1783, is now an establishetl 

fact. =\ complete and accurate description of Th~inax, under the binomial T. pat~viflo~a, has been 

found in an unpublished manuscript belonging to 

the younger Linnaeus. The manuscript reproduced in part in Figure 2 is clearly the source ol 

the binomial, antl whether Sivartz saw the manuscript before he ivent to Jamaica or upon his return is not known. Linnaeus’ description is a 

composite of Browne’s Coqpha I., Sloane’s illustration (pl. 213) and a specimen of an inflorescence 

preserved in the Banksian herbarium at the British 

Museum. Since the Linnaean manuscript was never 

published, we must consider only Swartz’s speciCorrespondence between Dr. Bailey and the Linnean 

Society of London in 1937, in a lcttcr signed by 5. Savage, 

Assistant Secretary, revealed that “no specimen of the species 

of Corjl~ha described by Patrick Browne in Hist. Jni?!. p. 190 

exists in the Linnaean Herbarium. In Linnaeus’ copy of 

Browne’s book there is no annotation by Linnaeus to show 

that a specimen of this plant was received by him with 

Browne’s herbarium.” 

’ Proritled by the courtesy of the Linnean Society, London, 

through Dr. H. E. Moore of Cornell I*niversity (List no. 40, 

“Ih n. /i 1. Palmarti in De icript iones”). 
4 SMITHSOSIAN COSTRIBUTIONS 10 BOTAKY 

FIGURE I.-Tlfrinas pnruipotn, cut and removed froin the forest for photographing, being 

examined 117 Dr. Itor Cornman. 
KUMBER 19 5 

men and his descriptions based on personal experience in Jamaica in typifying Thrinax pawiflova. 

The finding of the Linnaean manuscript is, however, 

of historical significance and provides answers concerning the source of the binomial and its meaning. 

Thrinax according to the manuscript is derived 

from the Greek 6giva5, which can be translated as 

“trident” or as indicated by Linnaeus “ventilabrum” meaning, “winnowing fork.” 

Thrinax was the tenth genus described in the 

Palmae after the publication of Linnaeus’ Species 

Plantarum in 1753. It should not then be surprising that a number of dissimilar and unrelated 

palms have been included in the genus (see Appendix I). The original description by Swartz in the 

Prodromus (1788) clearly sets down characters that 

are still diagnostic for the genus. The six-lobed 

perianth cupule, unilocular ovary, and infundibuliform stigma apply exclusively to the Thrinnx 

alliance. 

Early in 1789, W. Aiton reported in his Hortits 

Kewensis that there was a palm growing at Kew 

under the name of Thyinax parvipoia, which was 

introduced by Dr. William Wright upon his return 

FIGURE P.-Facsimile of a portion of Linnaeus the younger’s unpitblished manuscript on 

Thrinax paruipora. 
6 SMITHSOSIAK CONTRIBUTIONS TO BOTANY 

from Jamaica in 1777. The palm at Kew ~ias mentioned again by IV. T. Aiton in 1811, and again 

seventy-one years later by Hooker in the Kew Report 

for 1882. Thiinax was treated in the eighth edition 

of Linnaeus’ Genera Plantarum (edited by C. D. 

Schreber, 1791), and T. parviflora was treated later 

in the fourth edition of the Species Plantamm, 

edited by C. L. Willdenow (1799). 

In his magnum opus on West Indian plants, 

Swartz (1797:613-615) published a much amplified 

account of the genus and species in the Flora Indiae 

Occidentalis; flowers and fruit were illustrated on 

plate 13. 

The first mention of additional species in the 

genus Thrinax appeared in 1829 in Desfontaines’ 

Catalogus Plantariim (3rd ed.) where T. radiata 

and T. argenten appeared in a list without descriptions. The father and son team of J. A. and J. H. 

Schultes (1830) took up the Desfontaines names for 

which, with the addition of T. piimilio, they published diagnoses based on specimens sent by Loddiges, a nurseryman, to the botanical garden at 

Munich. hlartius (1838) elaborated on tlie clescriptions of T. parviflora, T. radiata, and T. al-gcntea 

and added two new species, T. miiltiffol-a and T. 

barbadensis. In 1845, nurseryman Loddiges, froiii 

whom Alartius also obtained several specific epithets, published a catalog of palms; there are no 

descriptions, thus the names that Tiere not already 

provided with diagnoses are nomina nuda. During 

the one hundred years between treatments by 

Rlartius and Bailey (1838 and 1938 respectively) 

forty additional epithets were attributed to the 

genus Thrinax. 

In 1866, A. H. Grisebach attempted to erect a 

new genus, Porothrinax, based on lh1inax piimilio 

of J. A. & J. H. Schultes. The lack of a separate 

diagnosis or description for a monotypic genus 

based on an old species does not satisfy the requirements of the present International Code of 

Botanical Nomenclature (see Appendix 11), so I 

am treating the genus as a nomen nudum. 

Charles S. Sargent (1899:88) made tlie first clear 

division of the genus when he recognized that specimens collected in Florida, and attributed to 

Thrinax, could be separated from that genus on 

the basis of the seeds being “vertically sulcate by 

the infolding of the testa into the ruminate albumin.” Thus he described Coccothrinax, a new genus 

based on C. jiiczinda Sargent. He also transferred 

Thrinux garberi Chapman into the genus to make 

a second species, C. garberi (Chap.) Sarg. He further suggested that Thrinax radiata and T. argentea both of Lodd. ex. J. A. & J. H. Schultes might 

also belong in the newly described genus, but it 

remained for K. Schuinann to make the formal 

transfers in 1901. Sargent (1899) divided the species 

remaining in Thrinax into two sections, the Peditellatae and Sessiliflol-ae, and described two new 

species, T. floridana and T. keyelzsis. 

In 1883, Bentham and Hooker included Thrinax 

along with their newly founded Hemit hl-inax in 

the tribe Corypheae, but Drude (1887) reduced 

Hemithrinax and Porothi.iizax along with Euthl-inax as subgenera of Thi.inax. Thus it remained 

until Beccari (1907) produced his work on American Coryphoid palms. Beccari raised Hemit hrinax 

to full generic status again and divided the Corypheae into two subtribes: Eucorypheae, characterized by the perianth having two whorls and the 

ovary being three-locular or with three carpels; and 

Thrinaceae, with a periantli of a single six-lobed 

whorl and the ovary consisting of a single uniovulate carpel. He divided the genus Thrinax into two 

subgenera based on the degree of intrusion of the 

testa into the seed: Ezithrinax, including the earlier Porothrinax of uncertain identity, and Typh10- 

thririnx. No mention was made of Sargent’s earlier 

division of the genus based on pedicels. The genus 

as outlined by Beccari (1907) contained ten species 

that he considered good, including four new names, 

plus three names of dubious application. Beccari 

(1912) published a series of articles on the palms 

of Cuba in which he treated three species of 

Thrinax. A supplement to his earlier work, in 

English, was included in a larger posthumously 

published xiork in 1933 [“1931”]. 

’1 new genus, Sitnpsonia, based on Thyinax microcarpa Sarg., it-as published by Cook (1937); however, the requirements of Article 36 of the International Code of Botanical hTomenclatzil-e, 1966, 

were not satisfied and the genus was not validly 

published. 

Bailey (1938), in an attempt to clear up some 

identification problems among palms in horticulture, produced a comprehensive study on the genus 

Thrinax. He accepted ten species, which he arranged in two subgenera as suggested earlier b~ 

Sargent. In a review of Beccari’s work Britton 

wrote (1908:240) that, “This is probably the most 
SUhiBER 19 7 

difficult of the American palm genera to untlerstand,” to which Ba.iley (1938: 133) replied thirty 

years later: 

Any subsequent student of the genus will be sympathetic 

with this estimate; but many of the difficulties banish if 

one knows the plants in the field, has really good herbarium 

material, and does not assume he must necessarily recognize 

all the species that have been described. Differences one 

draws diligently from poor herbarium sheets may disappear 

in the living plant. 

The present author must agree with this, antl with 

Bailey’s earlier statement (1938: 133) concerning 

Thyinax paixipoi,a Sw. and T. nzicrocai,pa Sarg. 

that, “If the student understands these two, all tlie 

other species fall readily into place.” Unfortunately Bailey did not have an adequate understantling of T. payvifloya in Jamaica, hence the species 

there did not fall so readily into their proper 

places. 

Distribution and Ecology 

Palms of the genus Thi,inax occur only on alkaline substrate, specifically coralline sands or limestone outcrops, from sea level to about 1200 meters 

elevation. They are distributed from areas of strong 

seasonal drought with rainfall averaging 100-1 12 

cm per year (with no more than 6 months having 

rainfall less than 8 cm per month) to regions where 

the rainfall may reach 762 cm per year. Two species 

endemic to Jamaica-Thyinax pni-uipol-a antl T. 

excelsa-are restricted entirely to exceedingly welldrained sites far from the influence of salt spray. 

Thyinax radiata, in addition to Jamaica, is widely 

distributed in tlie littoral throughout the northern 

Caribbean and nearby shores of the Gulf Stream, 

and tolerates considerable exposure to salt-laden 

winds. The fourth species, T. mowisii, not found in 

Jamaica, is fairly tolerant of salt and, although 

usually at sites similar to tlie aforementioned, is 

commonly found farther inland beyond the worst 

effects of salt spray. 

Each of the three species in Jamaica is confined 

to one of three major environmental situations (see 

Asprey, 1959): e.g., Dry Evergreen TVoodlantl or 

Thicket, Lower Rlontane Rain Forest, and Littoral 

Woodlantl or Thicket. Species of Thyinax have not 

been found naturally in areas lacking limestone or 

alkaline sand, they are strict calciphils. 

-rHKINAX RADIhTA.-one Of the tWO most widely 

distributed species in the genus, T. ~adiatn, is found 

only in coastal areas on limestone and alkaline 

sand, under tlie influence of salt-laden breezes, 

throughout the Greater Antilles (excluding Puerto 

Rico). It is also found on many of the smaller 

islands to the north and wesr such as the Cayman 

Islands and tlie cays off the coast of Cuba and 

British Honduras, the Yucatan Peninsula of Xlexico, the Bahama Islands, and southern Florida. In 

nature this palm is confined to saline conditions of 

the littoral but where there is adequate rainfall 

(127-254 cm per year) throughout the year. This 

is also the most commonly cultivated species and is 

grown under various conditions of soil and moisture far from the influence of salt. 

In Jamaica, Thyinax yadiclta may occur in dense 

stands but is more coinmon in small scattered populations along most of the coastline from extreme 

eastern Morant Point along the north coast west 

to Negril lighthouse and south to Little Bay. A 

small population also occurs at Long Acre Point, 

near Black River, and another is believed to be 

on Big Pelican Cay some distance off the southern 

coast of Jamaica. 

In 1958, G. F. Asprey and A. R. Loveless described a new addition to their list of Littoral Dry 

Evergreen formations in Jamaica based on a population of Thi inax 1-ndinta situated at Galina Point 

on tlie north-central coast in the parish of St. 

Mary. This formation, which they called “Littoral 

Palm thicket,” occurs on a raised coralline limestone shelf, 3.05 to 7.62 in (10 to 25 ft) above sea 

level. The shelf is relatively flat, devoid of soil, and 

is exposed to the full force of strong salt-laden 

trade winds. The sea is frequently rough and 

breaks over tlie low cliffs to produce a splash zone 

up to 12 meters broad. The species forms a characteristic feature of the littoral hedge, becoming 

increasingly plentiful on the landward side, “where 

it would appear to take the place of Littoral Evergreen bushland, but no explanation as to why this 

occurs can be offered” (p. 560). The authors further pointed out (p. 560) that 

Asprey and Loveless (1958) failed to distinguish between 

T. pnrzli/7orn Sic.., a conspicuous element in their studies on 

the Dry Evergreen thicket of Portland Ridge on the south 

coast, and the \ery different T. rndintn at Galina Point. 
SMITHSONIAN COSTRIBUTIOSS TO BOTANY 

The raised limestone beach is dominated by Thrinns pnrviflora [sic] to the exclusion of other plants. The trces grow 

out of fissures in the bare soilless rock and vary in height 

from 73-12! m (25-40 ft). The) are spaced, on the average, 

about 1.2 m (4 ft) apart and form a closed canopy. The 

palm reproduces actively since seedlings abound and thc 

plant is evidently in a most favourable environment. 

4 somewhat similar situation occurs at Morant 

Point near the lighthouse where the palms form 

small stands in the thicket along the windward 

coast. Throughout the rest of its range in Jamaica, 

T. mdintn occurs as scattered individuals in coastal 

thickets within the range of salt spray. The dense 

stand at Galina Point is not unique, for of Florida’s 

upper Keys, J. K. Small (1925:53) wrote: “There 

the groLvth is phenomenal, or at least it was, before 

the lust for destroying every living thing reached 

these islands with the advent of civilized man. 

Thatch hammocks clothed large and small areas.” 

In some small low areas and on outlying ke)s the 

palms still dominate the landscape. 

In the paper by Xsprey and Loveless, a site at 

Fort Point on the eastern edge of Discovery Bay 

FIGURE 3.-The Cockpit County of western Jamaica, in the vicinity of Barbecue Bottom. 
NUMBER 19 9 

(Dry Harbour) was also described. Fort Point is 

approximately 36 miles west from Galina Point. 

Meteorological data used for both localities were 

based on records for Richmond Llandovery Sugar 

Estate, which is nearer to Fort Point than to Galina 

Point. The rainfall figures quoted were 55 to 70 

inches (139.7-177.8 cm) per year which, when compared with evaporation figures over the same period 

of seventy years, presents a condition where there 

are only 5 months in an average year when precipitation exceeds evaporation. It must be realized, 

however, that the utilization of such figures is 

indeed tenuous in a region where abrupt changes 

can occur in very short distances depending on the 

exposure and topography. According to the most 

recent rainfall figures, Galina Point, at the western 

edge of one of the wettest regions of the Island, 

has between 60 and 80 inches (152.4 and 203.2 cm) 

of rain per year, while Fort Point is in a region of 

considerably lower rainfall not exceeding 50 inches 

(127 cm) per year. 

The preceding observations are brought out beFIGURE 4.-Thrinax radiata, base of the caudex and low mound of surface roots, growing on 

exposed and eroded limestone in the Florida Keys. 
10 SAlITHSONIz4N CONTRIBUTIOSS TO BOTANY 

cause even as Asprey and Loveless noted (1958: 

561): “The only major anomaly in the data is 

brought about by the megapliyllous palm Thiinax 

parviporu Sw. [sic].” Had they recognized that the 

palm from Galina Point was distinct from the palm 

in their Portland Ridge studies, a very important 

fact would have been realized and quite different 

conclusions might have been reached. Characters 

for separating the two species are in the key to the 

species in the taxonomic section: however, a very 

important characteristic, not in the key, is the fact 

that T. radiata is a true halophyte and T. parviflora is not. Further, T. mdiata occurs only where 

regular deposition of salt is accompanied by regular high rainfall. Thiinax paiviflora on the other 

hand occurs not at all where saline conditions prevail but can survive very dry environments. The 

present author agrees with the observation made 

by Asprey and Loveless (1958:562) “that the vegetation reflects the climate far more accurately than 

any meteorological data.” 

It seems appropriate here to point out a few very 

important differences between the two localities 

studied by Asprey and Loveless on the north coast 

of Jamaica, which bear on the ecology of Thrinux 

radiata. Galina Point is exposed directly to the full 

impact of strong trade winds and heavy seas. Ample 

rainfall is indicated by its proximity to the highrainfall zone of Portland and by the character of 

the vegetation in the immediate vicinity beyond 

the reach of the salt spray where herbaceous ground 

cover is plentiful. Asprey and Loveless noted (1958: 

561) that, “The presence of Philodendron sp. 

[ Iacertim] among the fringing woodland plants 

indicates a moist habitat,” from which they concluded that “the relationship of Palm thicket to 

rainfall distribution might repay further investigation.” A further observation by the authors (1958: 

562): 

In view of the fact that the rainfall along the stretch of 

coastline in which Fort Point and Galena Point are situated 

is more than twice as much as at Port Henderson, although 

the monthly distribution patterns are similar, it might at 

first sight seem surprising that Evergreen bushland is found 

at both centres. 

FIGURE 5.--Thrinax radiata in Jamaica: A, near the lighthouse at Morant Point; B, plants exposed 

along the limestone shelf at Galina Point. 
SUhIBER 19 11 

This is not surprising, for they did not in fact find 

bushland at Galina Point, it was displaced by palm 

thicket, and the bushland described at Fort Point 

is in a much drier area than Richmond Llandovery, 

where the rainfall records were made. The authors 

relied too much on interpolation of rainfall data 

and included too extensive a stretch of north coast 

in their data. Furthermore the additional effects 

of strong constant winds in conjunction with salt 

would produce drought conditions in the spray 

zone more intense than might be indicated by rainfall figures, no matter how accurate. 

A short distance away, to the west of Discovery 

Bay in the vicinity of the Queen’s Highway, 

Thrinax radiata occurs under what appear to be 

pessimum conditions for the species. Several widely 

spaced individuals are growing on the seaward 

side of the highway on a flat limestone terrace 

where there is an accumulation of sand and decaying vegetation. Evidence of low rainfall can be 

seen in the abundant xerophytic vegetation containing plants such as Agave hart isii, Eztphot bin 

punicea, and Plitrneria jamnicensis, which become 

increasingly abundant on bare rock toward the east 

in a thicket of semideciduous trees and shrubs. 

Coccothrinax jamaicensis, a palm otherwise limited 

to the drier thicket vegetation along the south coast 

(Read, 1966), occurs in abundance along the eastern 

portion of the Queen’s Highway. To.ivarc1 the western end of the Highway, halfway between Discovery Bay and Bengal Bridge, the climate changes 

rapidly to a more moist environment containing 

none of the species mentioned as characterizing 

the dry thicket toward the east. A single plant of 

T. pat-viflora stands out conspicuously in the ecotone on the inland side of the highway. On tlie 

seaward side of the highway Coccothrinax persists 

farther west among the plants of T. 7aclintc2, .\\.here 

it appears to tolerate increased moisture under 

saline conditions. It has been the author’s experience with palms in cultivation that many species 

which occur naturally in a very dry climate also 

have a high tolerance for saline conditions; e.g., 

species of Waslzingtonia, Erythen, Hyphnene, Phocnix. That is not to say that the converse is also 

true, for it is not. 

At the westernmost end of Jamaica between 

Orange Bay and Negril there occurs a variety of 

habitats in a region of fairly regular, often high 

rainfall. On Orange Point, Thi inax radinta thrives 

on a limestone ridge a few feet removed from the 

weatherit orn, absolutely soilless, clinker-type dogtooth limestone. Farther south along the shores of 

Bloody Bay and inland from Kegril Beach the land 

is low, almost flat but slopes imperceptibly into 

the nearby Great Morass. The substrate is white 

sand, with a very high water table, and Thr~nnx 

tcidzata occurs as scattered individuals along tlie 

better chained rise, only a few feet above sea level. 

The species is fairly common along the high cliffs 

near the Kegril lighthouse and occurs as scattered 

individuals southeastward to Little Hay and Long 

Acre Point. 

THRINAX ExCELsA.-This is a Jamaican endemic 

which is iery restricted in its distribution, occurring only in the region of the John Crow Mountains 01 the easternmost parishes of Portland and 

St. Thomas, and on Uncommon Hill, a limestone 

outcrop on the lower slopes of the Blue Mountains 

above Fruitful Vale in Portland. Its environmental 

requirements are rather unusual in that it is limited to the driest, best drained, most exposed situations in the wettest part of Jamaica. According to 

Asprey and Robbins (1953), the John Crow Mountains are clothed with lower montane rain forest 

on the lower slopes, Mhere the rainfall may be as 

much as 762 cm per year. 

That the vegetation is very characteristic of the 

substrate and drainage is strikingly illustrated by 

the situation in the John Crow AIountains. In the 

vicinity of TVinchester Peak at the southern end 

of the range, the deep heavy soil on the lower 

slopes supports a tall forest with a dense canopy. 

In the relatively low illumination, epiphytes are 

rare and the undergrowth consists mainlj of seedlings, some ferns, and a few herbaceous plants. 

Higher on the steep slopes below the peak, the 

well-drainetl substrate consists of a mixture of soil, 

decajing matter, and loose broken rock. The forest 

here is lower and more open with smaller more 

slender trees but with occasional large emergent 

trees. Ferns and herbaceous plants are more common in the increased illumination and abundant 

mcisture. At elevations between 304 and 762 m on 

the slopes and ridges throughout the range the 

foundation rock is frequently exposed, particularly 

along water courses. It is peculiar that in such a 

wet environment the exposed rock is usually devoid 

of vegetation other than the palm Thrinax exrelsn, 

which dominates the forest on nearly all exposed 
12 SMITHSOSIAN COSTRIBUTIONS TO BOTANY 

solid rock. Winchester Peak, at the southern end 

of the John Crows, receives less rain than elsewhere in the range. The southeast face of this peak 

is dominated by a palm brake of T. excelsa at between 457.2 and 533.4 m elevation. 

Throughout the rest of the range of the John 

Crow Mountains the forest is considerably more 

dense and more typical of lower montane rain 

forest, than that just described, because of the 

greater rainfall. On Uncommon Hill in the northeastern foothills of the Blue Mountains and in the 

John Crows, where the rainfall is consistently high, 

T. excelsa occurs only on rock outcrops at the 

higher elevations. An exception was more recently 

FIGURE 6.--Thrinax morrisii in the pinelands of New Providence in the Bahamas. This species 

is found in almost identical associations on Big Pine Key in Florida. 
KUXIBER 19 13 

found on a rocky hill near the mouth of the Rio 

Grande. 

THRINAX MORRISII.-~~ith much the same range 

as Thrinax radiata, this species extends farther 

east to the Virgin Islands and Anguilla, but it is 

conspicuous by its absence on both Hispaniola and 

Jamaica; however, the tiny island of Navassa, situated immediately between tlie two much larger 

islands, supports a small population of T. mol-risii. 

In Puerto Rico and Cuba the species is common on 

limestone hills of the interior where it occupies 

habitats apparently paralleling those of T. parviflora in Jamaica. Occupying a niche which seems 

to be intermediate between T. pai.niflol-a and T. 

~adiata, the Morris palm apparently cannot compete with either. Although somewhat tolerant of 

saline conditions, T. morrisii does not readily compete with T. radiata except on the smaller islands 

where annual rainfall probably falls below the 

minimum necessary for survival of the latter. Intermittent periods of rigorous drought may also restrict competition from T. mdiata. Thrinax morrisii exhibits a very wide range of tolerance for 

extremes of climatic conditions. 

As might be expected from a species that has 

two synonyms in Puerto Rico, two in Cuba, and 

two more in the Florida Keys, Thrinax mowisii is 

morphologically very variable; however, there does 

appear to be a pattern suggestive of more than a 

single genotype. Considerably more research is 

needed before anything more definite can be written concerning the delimitation of subspecies. 

One of the earliest reports of ecological consideration and competition between palms and other 

plants appeared in a discussion of T. ponceana by 

Cook (1901:536): 

Many of the palms are scattered among the taller shrubs 

and trees wherever there is sufficient soil and water to permit these to grow and yet not enough to give them exclusive 

possession, but on many of the drier and more sterile higher 

slopes the advantage is with the palms. 

THRINAX PARVIFLORA.-h the broadest sense this 

species occurs on nearly all exposed and eroded 

“Jamaican Hard White Limestone” throughout the 

western two-thirds of Jamaica. Along the southern 

part of its range Thl-inax pa?-viflom is a conspicuous element of the formation described by Loveless 

and Asprey (1957:813) as “Dry Evergreen Thicket,” typified by the vegetation of Portland Ridge in 

the parish of Clarendon. Thrinnx parviflorn ’isas 

described as “The commonest member,” of the 

shrub layer, “. . . which although capable of growing much taller, does not do so in this community 

except where there is a gap in the canopy.” These 

authors included the species as the principal representative of the Palmae among the five most important families of arborescent species in the Dry 

Evergreen Thicket. Apart from the presence of the 

“thatch,” the formation is characterized by the 

absence of herbaceous ground cover and terrestrial 

ferns. The substrate is generally deeply eroded bare 

rock with occasional pockets of shallow soil and 

very little humus. “Epiphytes are not well developed but are represented by tivo xerophytic species, 

the bromeliad Tillandsin fascicitlafa antl the orchid 

B1-oztghtonia sangitinen.” Dry Evergreen Thicket is 

a widespread formation on most of the hills and 

ridges of low to middle elevations from sea level 

to about 457.2 m (1500 ft) where the limestone is 

naturally exposed. Local variations in floristic composition result from local changes in topography 

and edaphic conditions. 

Areas of dry evergreen thickets on Dallas hlountain, Long Mountain, lower llolynes hIountain, 

antl Ferry Hill in St. Andrew represent the easternmost part of the range of T. pnwifloio. The Hellshire Hills of St. Catherine; Portland Ridge, Brazilleto hlountain, antl Round Hill in Clarendon; 

and the low irregular hills which rise along the 

northern edge of the St. Catherine and Clarendon 

plains, all support a dry evergreen thicket formation which continues northward past Juan de Bolas 

and llocho hlountains, hlende7 and Point Hills 

to the slopes of hlt. Diablo. This same formation 

containing T. painiflorn continues along the base 

of the May Day Mountains in Manchester froin the 

vicinity of Clarendon Park south past Round Hill 

and west toward Alligator Pond, then north along 

the southivestern escarpment of tlie Don Figuero 

lfountains in the vicinity of Gutters and Spur 

Tree. In St. Elizabeth a small area near Bull Savanna in the Santa Cru7 Mountains represents the 

only significant population in that parish. 

In a few places at low elevation such as Cane 

River Gorge, where cool moist air flows down from 

the Blue Mountains, the physical environment is 

modified by the lower temperatures and increased 

atmospheric moisture causing the formation of 

clew and fogs or increased rainfall. Somewhat similar conditions seem to exist along the Rio Cobre 
14 ShfITHSONI.4S COKTRIBUTIONS TO BOTAKY 

in the gorge between Bogwalk and Spanish Toivn 

and on the eastern slopes of the mountains near 

Clarendon Park. In the extreme southwest of 

Jamaica lies Negril Hill, a long low ridge running 

parallel to the south coast in a region of moderate 

precipitation 127-190.5 cni (50-75 inches) per year. 

Thrinax parvifloiu occurs here at the westernmost 

limit of its range as scattered individuals between 

New Hope Estate and Rivival. Similar populations 

occur to the north along the eastern edge of the 

Great Morass near Silver Spring, Hanover. 

Areas of frequent drought, described as Dry Evergreen Busliland by Loveless and Asprey (1957, 

support only the more drought resistant palm 

Coccothrinax jamaicensis in the ecotone between 

the two vegetation formations where it replaces 

FICURF 7.--Thrinax paruiflora growing in a siyal field near 

Palmer's Cross, Clarendon, Jamaica. Notc the heat) texture 

and coirupated armearance of the IeaFes. 

T. puivifloia. This is the situation east of Cane 

River in St. Andrew; south of May Pen, Clarendon; 

the western end of Portland Ridge; and between 

Gut River and Alligator Pond in Mancliester. Between Black River and Savanna-la-mar, an area 

with less than 88.9 cm (35 inches) of rain per year 

and subject to long drought, T. pa?vzflora is absent 

and Coccothrinax jamaicensis occurs only near the 

parish boundary shared by St. Elizabeth and Westmoreland. 

At Lances Bay in Hanover, an area of high rainfall with over 190.5 cm (75 inches) per year, a few 

individuals of T. pnrviflora have been found growing on the low rocky slopes overlooking the sea 

only a short distance from a population of T. 

7adiata. While the cliffs supporting the latter face 

northeast and are exposed to frequent salt-laden 

winds, however, T. parvifloia occurs only on the 

lee side of the ridge facing west. Along the north 

coast, T. pnruiflora has been found at only two 

localities near the sea: at White Bay, Trelawny, 

and along the Queen's Highway near Bengal Bridge 

in St. Ann. The region around 'IVhite Bay apparently experiences occasional drought since the vegetation consists mainly of logwood and thorn scrub. 

Rainfall is normally under 127 cm (50 inches) per 

year. The solitary robust plant of T. pnrviflora 

growing along the Queen's Highway stands among 

T. radiata and Coccothrinax jamaicensis. 

Ddphin Head, south of Lucea in Hanover, is a 

somewhat isolated mass of limestone rising to about 

548.64 m (1800 ft). Although dry evergreen thicket 

occurs on the lower cliffs, the upper ridge and 

peak are swept by clouds and support a dense 

woodland. Th?.inax paruifloru is a conspicuous element of the more exposed and higher levels of the 

mountain. A short distance to the east in the parish of St. James, T. parviflora has been collected at 

Bubby Hill under conditions similar to those on 

Dolphin Head. A single plant was seen near Hastings along the road to Maroon Town. It is curious 

that although conditions appear to be favorable for 

Thrinau, over the western Cockpit Country the 

species, with one exception, has not been collected 

or recorded anywhere between Deeside and Catadupa. The species no doubt occurs as widely scattered individuals, but the fairly evenly distributed 

and high rainfall of 190.5 to 508.0 cm (75 to 200 

inches) per year seems to be the limiting factor 

" II determining its exclusion. 
SUhIBER 19 15 

In the vicinity of IVindsor Cave, Trelawny, 

sharply eroded limestone hills form both the northern edge of the Cockpit Country and the headwaters of the Martha Brae River. The annual rainfall in the area averages between 127 and 190.5 cm 

(50 to 75 inches) and appears to be fairly evenly 

distributed throughout the year. The ridges are 

heavily wooded and T. pal-vipora occurs as widel) 

spaced individuals; however, the palm reaches its 

best development on exposed cliffs. 4 short distance to the north where the rainfall is much less, 

about 127 cm (50 inches) per year, the hills and 

ridges support larger populations of the species 

near Nt. Pantrepant and Sherirood Content nhere 

typical dry evergreen thicket again prevails. 

The eastern portion of the Cockpit Country is 

characterized by a region of jagged limestone pinnacles and interconnecting ridges 457.2 to 548.6 m 

(1500 to 1800 ft) in elevation which set off huge pits 

or “bottoms” often having vertical walls 60.96 to 

152.4 m (200 to 500 ft) high. Thi-znax pn?vlffo~n 

again assumes a conspicuous place on the top of 

each pinnacle, ridge, and cliff as at Mango Tree 

Hi1l.l Frequent rains permit a rather dense wootlland at all places where soil or humus can collect 

in the “bottoms” and on the slopes betTveen the 

pinnacles. A peculiar antl most interesting situation 

exists in the huge cockpit extending from Barbecue 

Bottom along the road to Burnt Hill. This is fully 

described elsewhere. 

East of the Cockpit Country is a region called 

the Dry Harbour Mountains which closely resembles the Cockpit Country but differs principally in 

the more extensive scrubby to thicket vegetation 

and higher elevations. This somewhat drier, rather 

inaccessible region supports a large population of 

Thrinax on the numerous ridges and pinnacles, 

particularly in the neighborhood of Albion Mountain. The lower elevation in the vicinity of Pedro 

and Grierfield supports a heavily wooded vegetation and relatively fewer Thl-inax. Scattered plants 

occur in the vicinity of Browns Town where limestone is exposed, but along the northern escarpment the annual rainfall increases steadily toward 

the east where 190.5 to 254 cm (75 to 100 inches) 

of rain per year may prevail. Thyinax pa~viflo~a is 

\$’hen questioned concerning a name for hlango Tree 

Hill, the local farmers gave the name “Carambi Hill”; however, “Mango Tree Hill” is the name coined b~ G. R. Ploctor 

of the Institute of Jamaica. 

found only occasionally near Bamboo and is rare 

on the cliffs of Fern Gdly. North and east of a 

line from Bamboo through Claremont, Moneague, 

Guys Hill, Glengoffe to Stony Hill, Thyinax does 

not occur except as individual outliers such as that 

at Fern Gdly, no doubt because of a lack of proper 

substrate antl the effects of increased rainfall. It is 

now clear, after comparing the distribution of T. 

parviflora with a rainfall distribution map, that 

the greatest concentration of plants of the species 

is to be found in the region classified as having 

127 to 190.5 cm (50 to 75 inches) of rainfall per 

year with numbers decreasing rapidly as rainfall 

increases above 215.9 cm (85 inches) per year or 

decreases below 101.6 cm (40 inches) per year. 

Optimum rainfall for T. pawipo~a must then be 

101.6 to 203.2 cm (40 to 80 inches) per year. 

In the center of the Island betlveen the fertile 

rolling cattle country of Claremont and the rich 

valley of St. Thomas in the Vale (Ewarton-Linstead) 

lies hlt. Diablo, a mass of limestone rising gratlually from the north to over 914 m (3000 ft) near 

the parish boundaries of St. A-inn antl St. Catherine. 

An extension running to the northeast forms a 

range of irregular limestone pinnacles (herein referred to as the Devils Backbone) about 762 ni 

(2500 ft) in elevation along the parish boundary. 

The principal mass of 5It. Diablo terminates in a 

very steep escarpment about 609 in (2000 ft) high 

along the southeast and west, overlooking Ewarton 

and Worthy Park respectively. X spur projects to 

the south and connects with a system of hills, of 

which Point Hill and RIendez Hill are a part, and 

encircles the valley of St. Thomas in the Vale to 

the gorge of the Rio Cobre. Thrinax pn~viflorn 

occurs on almost all exposed limestone and great 

numbers cling to the walls of the gorge. 

The vegetation above 548.64 m (1800 ft) elevation on hlt. Diablo and associated slopes, which are 

frequently bathed throughout the year in morning 

clouds and mists, most closely conforms to the formation described by J. S. Beard (1955) as “Dry 

Evergreen Woodland.” Perhaps a new formation 

to be called Montane Dry Evergreen IVoodland 

would be preferred, since Beard’s formation applies 

primarily to the lower elevations and not to those 

influenced by clouds and mists. Thrinax parvipol-a 

occurs on the more exposed cliffs and nearly all 

of the higher peaks, e.g., Hollymount, Grier Mount, 

Blue AIountain, Devils Backbone. The environ- 
16 SMITHSONIAS CONTRIBUTIONS TO BOTANY 

ment is perpetually moist and temperatures are 

normally in the 20s ("C) or often lower. Softleaved epiphytes are quite numerous on the tree 

trunks and rocks where a lush growth of moss, 

miniature orchids (Pleurothallis, Lepanthes), and 

delicate ferns often obscure the substrate. HohenDergia polycephala and Vyiesea platynema, bromeliads requiring a somewhat drier environment, are 

restricted to the upper level of the canopy. Gzumania erythrolepis, G. lingzilata, and Vriesea ringens require cool moist conditions and are common 

on the rocks and lower parts of the tree trunks. 

The limestone outcrop upon which mature 

plants of T. parvipora are localized, occurs as 

ridges and small peaks with intervening valleys of 

deep heavy soil or scree slopes. Although Thl.inax 

FKXRK 8.--Thritinx parviflot-a growing at about 914 m elevation on Jlt. Diablo. Sote the open 

crown and peculiar form of the leaves. Thesc plants and those in Figure 7 probably represent 

the two greatest extremes of phenotypic variability of the species. 
KUhIBER 19 

seedlings are plentiful on all types of soil, they are 

not known to reach maturity except on the stable 

rock outcrop where similar lithophilus species such 

as Euphorbia punicea and Plzimeiia marchii grow. 

Similar environmental conditions are met with on 

nearly all high limestone peaks and ridges such a5 

Albion hlountain, Top Hill, Somerset, and Dolphin 

Head. 

The foregoing is a general account of the distribution and ecology of Th1inax paruzfloin in Janiaica. Further details of the behavior of this species 

in two series of habitats where special ecological 

features can be recognized are described elsewhere. 

Morphology 

The genus Thyinax, in common with Heirzitlri inax, Coccothrinax, Zombia, and Haitiella of tlie 

Thyinax alliance, is distinguished from all other 

palms by having bisexual floivers in ivliich the 

perianth consists of a single irregularly lobed cupule. The genus is further distinguished fro111 Corcothrinax, Zombia, and Hnitielln by the splitting 

of the base of the petiole in the region ol' the 

sheath (Figure 9c). From HemiLhi.innx it is zipparently separated solely on the character 01 the 

stamens. Hemithrinax with subsessile anthers, a 

broad connective, and extrorse dehiscence is in need 

of additional intensive study, but adequate material of the different species is lacking at present. 

During this study certain characters, mainly of 

a quantitative nature and formerly believed to be of 

diagnostic importance, were given particular emphasis in order to test their useiulness as diagnostic 

characters. The literature is full of descriptions in 

which the size of the various organs (usually l'roiii 

a single incomplete specimen) is all one has for 

comparison of taxa. Good qualitative characters 

were all but lacking. 

mature flowering size plants were considered in tlie 

data presented. Whenever possible, specimens were 

taken from all accessible plants in a particular 

locality (measurements and specimens were collected from every plant exhibiting an inflorescence 

at some stage from anthesis onward even if the 

fruit had fallen already). Local populations consisted of all the plants in a particular niche or 

environment, e.g., a rocky pinnacle, gully, cliff, or 

hillside. These are usually of limited si~e; howSELECTION OF SAkZPLES FOR h~EASLJRE1\IEXT.-Onl). 

ever, if the population was extensive the collections consisted of all the material that could possibly be collected during the time available in one 

or more trips to the area. 

In order to study the species in every conceivable 

environmental situation at all elevations in Jamaica, a great deal of time was devoted to exploring 

the island in search of new localities. This was 

necessary in order to describe the range of distribution and the range of tolerance of each species. 

It was also necessary to collect representative specimens from as many different localities as possible 

in order to eliminate the bias caused by information from classical collecting areas. 

As much information as possible was obtained 

from herbarium specimens early in the study, but a 

concerted effort was made to re-collect in the localities represented by existing specimens in addition 

to the numerous new localities. It should be noted 

that herbarium specimens rarely if ever contain 

complete leaves or inflorescences. The most conimonly occurring materials on herbarium sheets 

usually comprise one or more of the lower primary 

branches of the inflorescence at some stage betneen 

anthesis and maturation ot the fruit but rarel) at 

either of these stages, and fragments of a single 

leaf, most commonly juvenile, Jvithout petiole or 

sheath. Most frequently if a petiole is present it 

and the hastula, and the blade, are split in two 

rendering them fairly useless for measurements. 

hIeasurements of the length antl diameter of the 

caudex were made at the time and on the plant 

froin which leaf and inflorescence specimens were 

taken. The specimens consisted of one complete 

inflorescence (usually cut at the sheath level, if 

the plant \<as not cut down), two fully expanded 

leaves with full petiole, two fully mature sheaths, 

antl one unexpanded bud leaf. The leaves comprised the most recently expanded leaf blade and 

one of the older but still whole leaves. About half 

of the segments were removed from the blade and 

discarded by cutting them several inches above the 

liastula and slightly to the side of the central 

group of segments. 

In order to achieve as much uniformity as possible in the data from both field and herbarium 

collection, where the apical portion of the inflorescence was usuall) either badly damaged or missing, it was necessary to restrict tlie collection of 

data to the five lowermost primary branches on 
18 SMITHSOKIIAN COSTRIBUTIONS TO BOTANY 

FIGURE S.--Thrinnx pawi/lorn: A, bud region showing indumentum on the leaf sheaths and 

internodes; R, the same as A but demonstrating how the inflorescence emerges from the split 

sheath and arches out beneath the subtending leaf petiole; c, thc same as in A but a heavier 

caudex showing more clearly the broad split which distinguishes the genus from Coccothrimx; 

D, a single primary branch with its numerous flowers at anthesis. 
NUMBER 19 19 

each inflorescence. In the calculation of inflorescence length (length of exposure above the sheath 

apex), number of primary branches per inflorescence, primary branch rachis length, number of 

ultimate branches per primary branch, and the 

length and diameter (at the point of insertion on 

the rachis) of the ultimate branches, all parts of 

the five primary branches were measured; however, 

since the number of flower or fruit pedicels per 

primary branch is excessively large a random sample was necessary. This was achieved by randomly 

selecting five ultimate branches from each of the 

five lowermost primary branches per inflorescence. 

The ultimate branches on each primary branch 

were numbered from the base to the apex along 

the rachis. These branches were randomly selected 

by placing a pointer on some digit in the table 

(1.2) of Snedecor’s (1948) table of random digits. 

That digit and the one following it, be it “01” or 

“25,” indicated the branch to be sampled. If the 

number was greater than the number of branches 

present, a second combination of digits was necessary. Once the branches were chosen all pedicels 

on each branch were measured. 

CAvDEx.-The caudex of Thrinax is columnar 

and nearly uniform in diameter throughout its 

length but tapers almost imperceptibly toward the 

apex, while the base is often noticeably expanded 

2 to 5 dm above the substrate by the production 

of masses of tough wiry roots. It is not uncommon 

to see plants with large mounds of exposed roots. 

The caudex may be gray or tan and is roughened 

by alternating smooth internodes and slightly raised 

leaf scars. As the palm ages the length of the internodes being produced is much reduced, eventuall) 

becoming a mere line encircling the apical portion 

of the caudex in tall plants. The leaf bases are 

persistent for some time following the death of the 

leaf and are always conspicuous below the crown. 

Within the tightly congested overlapping leaf 

bases the internodes are velvety tomentose (Figure 

A striking feature of plants of T. parvipoin when 

growing at the higher elevations is tlie very tall 

slender caudex; however, measurements from a 

number of populations throughout the range of 

the species show that there is great variability in 

caudex height and diameter even lvi thin local populations. The range of variation in caudex height 

of 86 individuals of Thiinnx pni-riiflo~cl from among 

9A). 

19 different localities ,j is 1.0 to 10.0 (-13.0) in. The 

mean heights for each locality varied from 1.5 to 

10.0 m. These figures are to be compared to 

(1.0-)1.5 to 7.5 (-12.0) (Yz4.0) m for T. radiata 

(51 samples) and 3.5 to 9.0 (-11.0) (F=G.5) m for 

T. excelsa (25 samples).O The range of variation 

in caudex diameter of tlie same individuals of T. 

paruiflora mentioned above is 5.0 to 14.0 (-15.0) 

cm. The mean diameters for each locality varied 

from 6.0 to 12.5 cm. These figures are also to be 

compared to (7.5-)8.0 to 11.0 cm (X=9.0 cm) for 

T. radiata and 12.0 to 16.0 cin (Y=14.5 cm) for 

T. excelsa. 

LEAF.-sheclth: The fully expanded leaf of 

Thrinax is composed of four principal parts: blade, 

hastula, petiole, and sheath. The mature sheath is 

at first tubular and encloses the younger tleveloping organs. The sheath has no doubt been the 

most neglected portion of the palm in the making 

of herbarium specimens and in studies of palm 

morphology. Although it has not been fully exploited as a diagnostic character, the forin of the 

leaf sheath is of utmost importance in distinguishing Thrinax and Hernithiinax from their closest 

allies Coccothrinax and Zombia. Even very young 

seedlings can be recognized by examination of the 

leaf sheath. Coccothrinax and Zornbicl have leaf 

sheaths which at maturity are still completely tubular with the solid petiolar base continuing unchanged to the point of insertion on the caudex. 

The netlike tubular portion of the sheath retains 

its appearance long after the blade has died and 

broken off. 

The mature leaf sheath of Thiinnx and Hemithrinnx is, however, quite different from that described for Coccothrinax and Zombia. The petiole 

on entering the sheath portion is divided basally 

in the form of an inverted wedge or ,I, (Figure 9c). 

The fibrous portion is netlike at first as in Coccothl-inax but soon breaks down and becomes 

ragged or loosely fibrous. The conspicuously split 

5The localities mentioned are from among those cited in 

the study of pedicel length and mapped in Figure 41. 

Thriiinv morrisii is escluded from these figures as it was 

not included in the original intensive study. Considering the 

extensive range of the species, the small amount of data 

available would perhaps be misleading by comparison. More 

complete data and bargraphs depicting the range of variation and means of the individual localities for Thrinnx 

fmi~iflorn can be found in Read (1968). 
SMITHSOSIAS COSTRIBUTIONS 7 0 BOTANY 

petiole bases persist below the crown long after 

the fibrous wrapping has deteriorated. 

The apical portion of the Thl-inax sheath is of 

great diagnostic importance within the genus. That 

of T. parviflol-a, T. excelsa, and T. morrisii is linguiforni (Figure IOA,B) extending upward from 

the point of attachment on the petiole and becoming long pointed. This tonguelike extension is clothlike, often separating between the fibers and then 

appearing as a net. The sheath apex of T. 7ndiatn 

on the other hand is not at all linguiform (Figures 

lOc, ll~) but takes an exactly opposite form with 

the margins descending from their attachment 

along the solid petiole in a V-form. The sheath of 

T. l-adiata soons tears away from the petiole, even 

as the leaf expands (Figure ll~), and the fibers 

readily separate into ragged fibers around the “bud” 

region. The lateral margins of the sheath may be 

inserted on the petiole base at the same or different 

levels. 

The lower portion of the sheath of all four 

species is covered with a dense velvety tomentum 

(Figure ~A,c) but is usually lost on exposure. As 

the young inner growth expands, the sheath fibers 

pull apart permitting the tubular portion to expand with internal growth pressures. The division 

of the petiole also separates. Even in the very inimature leaf sheath, a groove is present in the otherwise solid portion of the sheath. 4s the “bud” expands, the groove separates and in mature plants 

the opening of the split exposes the young inflorescence (Figure 9~), but of course this is normally 

FIGURE 10.-Leaf sheaths of the three Jamaican species of Thiinnx showing: A, B, the long 

linguiform apex of T. excelso aiitl T. pnivilloin ieqpecti\ely; c, the deep V-form, nonlinguifoim 

sheath of T. radiata. 
NUMBER 19 21 

obscured by the older, dead, outer leaf bases. As 

the inflorescence develops and elongates, it continues to separate the sides of the split petiole and 

extends through the opening. At maturity the inflorescence normally (in Jamaica) appears below 

the petiole of the leaf to which it is in fact axillary. 

Rarely does the inflorescence emerge above the 

subtending leaf petiole. 

Petiole: Petioles of Thyinax are slender, and 

extremely strong and flexible. They vary considerably in length, width, and form, even within a 

species. However, the length of the petiole in relation to the length of the longest leaf segment is an 

excellent character for distinguishing between T. 

radiata, wherein the petioles are shorter than the 

longest segment, and T. parviflora, with petioles 

longer than the longest segment of the leaf. The 

range of variation of petiole length of 218 samples 

of Thyinax parviflora from among 26 different localities is (35-)40 to 155 cm. The mean lengths 

for each locality varied from 40 to 135 cm. These 

figures are to be compared to (36-)44 to 88 (-94) 

cm (F=61.6 cm) for T. radiata (50 samples), and 

125 to 200 cm (j;=165 cm) for T. excelsa (6 samples). The range of variation in petiole width of 

the same individuals of T. parviflora mentioned 

above is 0.9 to 2.4 cm. The mean widths for each 

locality varied from 0.9 to 2.0 cm. These figures 

are also to be compared to 2.1 to 3.2 cm (X=2.5 cm) 

for T. radiata and 2.5 to 3.9 cm (?=3.4 cm) for 

T. excelsa. 

Throughout most of their length petioles of 

FIGURE 1 I.-Bud regions: A, Thrinax radiata; B, T. parviflora, showing the strongly linguiform 

sheath of the latter, Xote the minute scattered scales on the petioles in “A” and the absence of 

them in “B.” 
22 SMITHSONIAS COKTRIBUTIONS TO BOTAKY 

Thrinax are ancipitous and biconvex; however, 

the solid portion within the sheath is usually concave adaxially. At the junction between the petiole 

and the sheath they may be flat or slightly concave 

in T. paruiflora and T. excelsa or with a median 

ridge in T. radiata. The petiole is widest at the 

junction with the sheath and narrowest a short 

distance below the hastula, where its margins may 

be variously bent and distorted as the blade expands (Figure 12). 

The adaxial surface of the petiole is glabrous 

or glabrescent. The abaxial surface of the emerging 

petiole is densely floccose lepidote initially, but the 

degree of persistence of the indumentum varies 

among the species depending on exposure. The 

petioles of T. parviflora lose their scales very soon 

after exposure (Figure ~OB), while a conspicuous 

amount of scattered scales persists on the petioles 

FIGURE 12.-Three different iiews of the hastular legion: 

A-C, Thrinax radiata; D-F. T. parvipora. (A, D = side views; 

B, E = abaxial views; c, F = adaxial views.) 

of T. radiata (Figure 10c) and T. morrisii. The 

abaxial surface of the petioles of T. excelsa remains 

velvety for a considerable time (Figure 10~). 

Hastula: The first mention of the hastula, or 

ligule as it had been known to Beccari and others, 

as a key character was by J. A. & J. H. Schultes 

(1830: 1301). They stressed that the difference between their newly described T. argenten and the 

earlier T. paruiflora was that the former had a 

“prominentia centrali minore.” They also distinguished their new T. pumilio by its “defectu prominentia in centro frondis.” All members of the genus 

Thrinax exhibit a prominent adaxial hastula of 

one form or another. 

The hastula appears as an extension of the apex 

of the petiole into the laminar portion of the leaf. 

It is always in a plane with the petiole and overlaps the region of segment insertion but may bend, 

twist, or become semitubular depending on the 

degree of expansion or folding of the blade. The 

length of the hastular overlap was thought to be of 

some importance, but as a generic key character, it 

has been found of little use. The range of variation 

in hastula length of 164 individuals of Thyinax 

parviflora from among 26 different localities is 

(0.1-)0.4 to 4.6 cm. The mean lengths for each 

locality varied from 0.6 to 3.2 cm. These figures 

can be compared to 1.0 to 2.0 cm (Y= 1.4 cm) for 

T. radiata (20 samples) and 1.8 to 2.6 cm (y=2.1 

cm) for T. excelsa (6 samples). 

Although the shape of the hastula is quite variable, the general outline and proportions hold 

fairly true for each species but are extremely difhcult to describe. It is important to point out that 

the hastula is distorted by expansion of the leaf 

blade and is thus best observed on the unexpanded 

“bud leaf.” Occasionally the hastula may be torn 

by expansion of the blade. The shape and form of 

the hastula may be seen in Figure 12A,C,D,F. 

Abaxially the apex of the petiole usually terminates in a short overlapping collar of tissue which 

may exhibit one or two small prominences 1 to 2 

mm long. Throughout the habitats at the lower 

elevations, however, Thrinax parviflora commonly 

exhibits abaxial hastular projections of considerable size (Figure 12~) occasionally exceeding the 

adaxial hastula in length. Such prominent abaxial 

hastulas have not been observed in any other species of the Thrinax alliance. Leaves of a plant in 

the population of T. parviflom at Cockpit, Claren- 
NUhfBER 19 

FIGURE 13.--Thrinax parvipora, newly expanded leaf blade, with adhering scales: A, abaxial 

surface; B, adaxial surface. c, D, Abnormal processes from the abaxial hastular region, on plants 

found at Cockpit, Clarendon, Jamaica. 

23 
24 ShiITHSONIAS CONTRIBUTIONS TO BOTANY 

don, Jamaica, were found to possess exceedingly 

long, slender, rigid filaments arising from the abaxial hastula (Figure 13c,~). The filaments appear 

to be extensions of the retuse or slightly bifid 

minor prominences mentioned above. No explanation can be offered for this curious phenomenon 

at present. 

In bud, and upon emergence, the abaxial hastular region of the young leaf is densely covered with 

floccose lepidia, which are normally lost soon after 

exposure. The hastular collar is usually fringed 

with larger more persistent scales (Figure 13~,~). 

The newly exposed hastula of the T. moiiisii leaf 

is always densely velutinous with silvery-white 

tomentum. 

Lamina: The leaf blade of Thyinax and its close 

allies is completely palmate in form, having no 

central costa or primary midrib. Although of basically the same structure throughout the genus, 

the leaf blade assumes a number of different and 

characteristic forms. They also vary considerably 

in size, texture, and indumentum. 

The unexpanded leaf blade as it emerges from 

the “bud region” is a compressed bundle of tightly 

folded plicate segments with only the major nerves 

and segment margins exposed. The exposed surface 

is at first appressed lepidote, but after the blade 

expands as in Figure I~A,B, the scales persist for 

only a short time on the principal nerves. 

The leaf blade often has been inaccurately described as peltate because as the segments expand, 

as a result of pulvinus-like regions along the largest nerves in T. radiata and occasionally shade forms 

of T. @arviflo~u and T. moirisii, a complete circle 

is formed by the position of the segment apices, 

and the outermost segments overlap across the 

petiole (Figure 14). Leaves of mature T. paiviflora 

are normally so folded, crumpled, twisted, or curled 

that they present a three dimensional structure, 

which is described more fully elsewhere. The fully 

expanded leaves of T. excelsa are flat and nearly 

circular in outline, but the outer lobes do not normally meet nor overlap. 

Segments: Segment number in members of the 

Thrinax alliance has also been given importance 

as a key character. Although the segment number 

is fairly constant for the leaves of any given plant 

of T. parviflora, varying from three to five about 

the mean, the variation within a single population 

may be as much as 22 segments between the greater 

and smaller numbers. The measurements at locality 

No. 33 in Jamaica were found to cover nearly the 

entire range of segment numbers throughout the 

entire population in Jamaica and considerably 

overlap the numbers recorded for leaves of T. 

radiata and T. excelsa. There is no direct relationship between the size of a leaf and the segment 

number. Thrinax excelsa with a leaf 3 m broad 

may have 52 segments, while a leaf of T. @arviflora 

only 1.5 m broad may have a similar number. 

Leaves of juvenile plants normally have fewer 

segments than those of mature plants. 

The range of variation in segment number for 

264 samples of T. parviflora leaves, from among 28 

different localities, is 35 to 60. The mean number 

of segments for each locality varied from 37 to 56. 

These figures can be compared to 51 to 63 seg 

FIGURE 14.--Thvinax paruiflora at Palmer’s Cross, Clarendon, 

Jamaica. The region where the segments are joined is the 

palman; note the tubular hastula. 
SUllBER 19 25 

ments (X=56) for T. radiata (50 samples) and 

(52-)55 to 65 segments (X=59) for T. excelsa (41 

samples). 

Individual segments may vary in size, outline, 

and degree of fusion at the margins. The segments 

directly in line with the petiole are the longest 

and broadest within the leaf. Those on either side 

become progressively smaller away from center. 

The degree of segment fusion is also greater at the 

center where two or three segments may be fused 

for more than three quarters of their length or the 

two central segments may be fused for their entire 

length. 

Apart from the greater fusion of the central segments the amount of fusion between segments elsewhere across the blade is somewhat irregular. For 

purposes of comparison a specific region of the 

blade was selected to represent the leaf. Segments 

to be measured were chosen by grasping the central 

four segments in the hand and counting the next 

three segments on each side of the group held. 

The third segment on each side of the central 

group of segments (thus two segments per leaf) 

were selected and removed for measuring. In order 

to collect a maximum amount of information, concerning the leaf blade, with a minimum of bulk, 

the most satisfactory method was to strip the selected segments from the leaf, down to the hastula. 

The remainder of the blade was then discarded, 

except for the hastula, which was trimmed out and 

retained if undamaged. The segments thus selected 

from the same region on each leaf provided comparative information regarding the length, breadth, 

form, texture, indumentum, and length of connation. The liastular region (Figure 12) and accompanying segment bases provided additional information regarding tlie petiole width, hastula form 

and length, and the number of segments per leaf. 

The leaf segments have been described variously 

as lanceolate, ensiform, linear, etc., but these terms 

are more applicable to leaves or leaflets with curved 

margins. The margins of Thrinax leaf segments 

are straight throughout their greater length particularly in tlie proximal half. They may, however, 

have near the broadest region a pinching in or 

“shoulder” (Figure ~~A,c,E). The chart of simple 

symmetrical plane shapes published by the Systematics Association Committee for Descriptive Riological Terminology (Taxon 11, 1962) provides a 

much more accurate terminology of palm leafsegment outline. In the chart,? numbers 25, 54, 

and 63 correspond closely to the outlines of the 

leaf segments in Thrinax. These are basically narrowly rhomboid, but vary from trullate to obtrullate (Figure 15~,~). 

The leaf segments of T. parviflora are more often 

than not conspicuously pinched in just above the 

broadest part (Figure ~~A,c,E). This character is 

not peculiar to T. parviflora, however, for it is 

found in T. radiata as well, but it is not so prominent in the latter. 

Segment apices may be bifid to varying depths 

or not at all. In the leaf segments of T. parviflora 

the apices are usually acute and often not at all 

bifid. When bifid the apical points may be strongly 

divergent (Figure 15~,~). In T. radiata tlie segment apices are long and slender (Figure 15~,~). 

usually deeply bifid and attenuated into a filament 

which is readily lost. The outermost segments in 

all species may exhibit long, slender, fiberlike filaments up to twice their length. The occurrence of 

filaments in the sinuses between the segments (such 

as is typical of Sabal and Washingtonin) is rare; 

however, several leaves of T. parviflora have been 

found where similar but more delicate filaments 

were produced. What may appear to be a greater 

number of anomalies in T. parviflora should rather 

be taken as an indication that the greater the 

number of specimens examined in the field, the 

greater number of anomalies will be found. 

Although segment width as such is of little diagnostic significance, the position of the broadest 

part along the segment is very important. In 

Thrinax parviflom the broadest part of the segment is well above tlie sinus (Figure 15~). In both 

T. mdiata and T. excelsa the broadest point is at 

the sinus (Figure 15~), or very close to it. The 

measurement of segment width was always made 

at the broadest point. The range of variation of 

segment width of 398 samples of T. parviflora from 

among 29 different localities is 2.4 to 6.4 cm. The 

mean segment widths for each locality varied from 

2.4 to 5.6 cm. These figures are to be compared to 

(4.6-)4.S to 6.2 (-6.4) cm (X=5.6 cm) for T. radiata 

(50 samples) and (4.4-)4.6 to 7.2 (-7.4) cm (?= 

6.2 cm for T. excelsa (20 samples). 

The range of variation in leaf-segment length for 

Reproduced in tV. T. Stearn, Botanical Latin, pages 318- 

319, 1966. 
26 SMITHSONI.4S COKTRIBUTIONS TO BOTANY 

T. parrriflora is very great and overlaps considerably with T. radiata, which in general exhibits 

much longer segments. Those of T. excelsa on the 

other hand are very long and even at the lower 

limits of the range of variation measurements overlap with those of T. radiata only at the 5 percent 

level. The range of variation in segment length 

for 428 samples of T. pa~uiflora from among 30 different localities is 39 to 96 cm. The mean segment 

lengths for each locality varied from 42 to 92 cm. 

These figures can be compared to (73-)79 to 

113 (-115) cm (z=92.9 cm) for T. radzata (50 

samples) and 114 to 173 cm (X=144 cm) for T. 

excelsa (16 samples). 

Palman: The region of the leaf blade wherein 

the segments are fused together by their margins, 

measured from the hastula to the sinus between 

A 

I 

FIGURE 15.-Thrinax leaf segment outlines showing fusion 

(indicated by arrows): A, T. parvipora; n, T. radiata. c, E, 

Two types of constrictions on segments are depicted; D, F, 

bifid apices. 

the segments, is known as the palman (Figure 

15A,B, between points indicated by arrows) like the 

palm of the hand from the wrist to between the 

fingers. The palman has been described variously 

as one-third or two-thirds the length of the segments; however, in T. paruiflora it is so variable, 

depending on the age of the plant or exposure, 

that such descriptions are of no practical value. 

Actual measurements of the palman do, however, 

have some comparative value among the taxa. 

Measurements of the palman of each of the three 

Jamaican species are compared as follows: the range 

of variation in palman length of 749 samples of 

T. paruiflora from among 29 different localities is 

7 to 34(-42) cm compared to (30-)33 to 54(-55) 

cm for T. radiata (50 samples) and (48-)52 to 

84 (-100) cm for T. excelsa (16 samples). The mean 

lengths for the palmans for each locality of T. 

parzriflora varied from 9 to 28 cm compared to 44 

cm for T. radiata and 71.8 cm for T. excelsa. The 

length of segment fusion or palman depth was 

measured using the same segments described under 

length and width of leaf segments. 

Because, as previously mentioned, the central 

segments are fused for a greater length than the 

outer ones, the palman is narrower distally and 

toward the base than it is at the side. A common 

characteristic of the leaves of T. radiata is the complete fusion of the margins between the central two 

segments. Elsewhere in the blade the palman outline, formed by the sinuses, is fairly uniform. This 

latter is also true for leaves of T. excelsa and T. 

morrisii. In T. pa?-ui/?ora, however, apart from the 

cluster of central segments with conspicuously 

longer fusion, the length of the fusion between the 

segments is very irregular throughout the blade. 

Undoubtedly, the largest palman measurements 

for the genus are those of T. excelsa. They clearly 

exceed even the largest measurements of T. parviflora and overlap the very largest of the measurements of T. Yadiata by only a few centimeters: and 

the overlap in palman depth measurements between T. parviflora and T. radiata occurs only at 

the 5 percent level. Therefore palman width or 

depth can be used in part as a diagnostic character 

in Jamaica, providing of course only fully mature 

specimens are used and the measurements are 

made in precisely the same manner as those here. 

Indumentum: The adaxial lamina1 surface, except for the major nerves, is for the most part 
R’UhfBER 19 27 

glabrous or glabrescent. Minute scales may be 

found occasionally on the adaxial surface near the 

apical portion of the segments, especially on freshly 

opened leaves. Although a waxy surface is characteristic of palms throughout the Thrinax alliance, 

it appears that the leaves of T. paraiflorn and especially T. morrisii have a particularly great amount. 

One of the first peculiarities noted by the author 

in regard to T. fiarvifEo?a was an abundance of 

white “hairlike” material on the surface of the 

leaves in a number of herbarium specimens. On 

closer examination the material appeared as 

minute needlelike crystals, which dissolved in absolute alcohol. When drops of alcohol were washed 

across a leaf segment and allowed to dry on a piece 

of glass, a quantity of white waxlike substance resulted, The same held true for both fresh and dried 

Ah 

FIGURE 16.--Infiorescence bracts, the ultimate tubular bifid 

bracts on each primary branch: A, B, Thrinax parvipora, 

adaxial and side views; c, T. radiata, adaxial view; D, E, T. 

excelsa, side and adaxial ciews respectively; F, c, prophyl in 

position, on inflorescence axis, in the axil of the leaf sheath. 

Seed germination: H, T. excelsa; I, T. parvipora. 

leaves of T. pnrviflora. When the same experiment 

was run using leaf segments of T. radiata the 

amount of wax deposited was negligible by comparison. 

Abaxially the laminar surface is variously lepidote, the differences providing excellent diagnostic 

characters. AIthough the abaxial surface of the 

leaves of T. pawiflorn appears to be glabrous, it is 

in fact glabrescent with widely scattered microscopic scales which are readily lost with age. Unlike 

the other species, the scales on some specimens of 

T. pamiflora appear to be reduced to simple hyaline hairs or “Y-shaped” scales which become detached quite readily. A magnification of about 25 

times is necessary in order to see the scales on 

T. parviflora. 

The scattered scales on the leaves of T. radiatn 

are quite conspicuous and may be seen easily with 

the unaided eye as tiny flecks over the abaxial surface. On a fresh leaf the individual scales may be 

shortly fimbriate from an oval glandlike center. 

On drying or with age the fimbria may be lost 

leaving the conspicuous central portion which can 

be readily seen on herbarium specimens as well, especially with a 10-power lens. The abaxial leaf surface 

of T. radiatn may, in addition to the scales, be 

glaucescent, but it is never silvery white. 

Thrinax excelsa is readily distinguished from the 

aforementioned by having the abaxial surface of 

the leaf blade densely covered with interlocking 

fimbriate hyaline scales. Fully mature leaves of 

this species are conspicuously white to silvery white 

below as a result of the dense covering of hyaline 

scales. The leaves of juvenile plants of this species 

appear glabrescent but nearly always exhibit 

patches of interlocking scales and hairs. 

Among the widely distributed populations of 

Thrinax morrisii, the degree and development of 

abaxial scales varies considerably. Whether this is 

a reflection of the ecology or is truly genetically 

determined remains a question for further study of 

the living plants throughout their total range of 

distribution. Specimens from Anguilla, the type 

locality, appear depauperate and exhibit very 

small, poorly developed scales; one specimen 

nearly lacking scales altogether. Specimens from 

Puerto Rico through the Bahamas and Florida 

exhibit increasingly greater numbers of scales with 

greater and greater degrees of fimbriation on individual scales. In the Cuban plants the fimbria are 
SMITHSOXIAS COKTRIBUTIONS TO BOTANY 

greatly extended and often become interlocking 

much like the scales on leaves of T. excelsa but 

are not quite as densely arranged. 

INFLoREscENCE.-ktxis and Bracts: The inflorescences of the four species of Thrinax are basically 

of similar structure but differ markedly in size, 

puberulence of the branches, and color at anthesis. 

Originating in the axil of a leaf, at a point immediately below the petiolar groove, the inflorescence 

is adnate to the leaf for about 1 cm (Figure 16~). 

The first inflorescence bract is inserted about 2 cm 

above the base (Figure 16~). It is bicarinate, flattened adaxially and convex or rounded abaxially, 

and is completely closed at first. The apex is 

pierced by elongation of the second bract. 

The inflorescence of Thrinax and its close allies 

consists of a short weak axis with between 7 and 22 

primary branches supported mainly by large, fibrous 

tubular bracts telescoped one inside another from 

the apex to the base. Each bract, with the excepLN. 

# 

9 

30 

12 

5 

38 

31 

8 

10 

7 

27 

25 

15 

26 

2l 

2 

3 

18 

42 

34 

14 

17 

ut 

22 

29 

28 

40 

13 

16 

19 

- 

2 

250 

175-250 

756-900 

1,250-1,600 

400 

10-20 

40 

10 

500 

200 

L,500-1,650 

500 

250 

tion of one to several empty basal bracts, subtends 

a primary branch, enclosing the basal portion of a 

primary branch and the lower portion of the next 

higher bract. The apical aperture of each principal 

bract is oblique. The bracts are densely appressed 

lepidote varying in color among the species. In 

T. radiata and T. morrisii the scales are gray or 

white becoming tan with age; those of T. parviflo~a 

are light brown or tan at first darkening with age; 

and in T. excelsa the scales on the bracts are dark 

rusty brown. 

Measurements of the variation in inflorescence 

length within Thrinax parvifloru are recorded in 

Figure 18. The inflorescence in T. paruiflora usually equals the petiole in length but may occasionally exceed it, extending up among the leaf 

blades, but is not known to exceed the leaf in 

length. Inflorescences of T. radiata and T. morrisii 

are always longer than the leaves and extend conspicuously well above the crown of leaves. The 

..... w ............. ...... .. 

v ........... 0.. - ....... ......... .9 ...... .... V .................. ..... n 

D .............. - ........................... .. ................................. ...... ... ...... .................. ...... “ ........... ...... ......... .. Y .................................. ........ - ..................... .. - R .................. .... .. ....................... .......... w ...................... ..... - ........................ 

NO. 

TITS I 

I 

3 

I 

I 

3 

9 

5 

25 

I 

I 

25 

3 

I 

2 

2 

3 

1 

3 

I 

2 

I 

2 

4 

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25 

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2 

3 

1 

I 

- 

FIGURE 17.-Pedicel length, Thrinax parvipora, arranged by increasing means, top to bottom, 

showing the wide range of variability of this once “important” taxonomic character. The x in 

bar graphs represents mean length, solid line 90% of all measurements, and dots indicate 5% 

of total off each end of range. 
43 

24 

2h 

A. 1 

9. 

cb 11111111 

1111 

- 

w 

4C 50 60 70 80 90 100 UO DO 130 140 19 160 170 lf0 

Inflorescence length in em 

37 

24 

31 

A. 

B. 

C. 

5 10 15 20 

Number of primary branches per inflorescence 

25 

3 93 

263 

496 

1.3 2.0 3-9 4.0 5.0 

Pedicel length in m 

A. 

B. 

C, 

2.0 4.0 6.0 8.0 10.0 l2.0 14.0 16.0 

Length of ultimate branches in ern 

A. - I-*- 

B. 

C. 

- - -1 

1- w .-I 

39 

32 

50 

35 40 45 50 55 

Wmber of segnents per leaf 

60 

A. 

B. 

C. 

20 40 60 80 100 120 140 160 

Petiole length in em 

A. 

B. 

C. 

I. -1 

=- 

I.-, . 35 

24 

29 

0.2 0.4 a6 0.8 LO u L4 1h 1.8 2.0 2.2 2.4 

Petiole width at apex in em 

35 

21 

25 

A. 

B. 

C. 

2.5 5 *O 

Trunk diameter in em 

7.5 1.00 

FIGURE lS.-Measurements of characters from the three intensively studied populations in 

Jamaica: A, Hollymount Hill; H, Mango Tree Hill; c, Cockpit, Clarendon. Sample size on right; 

bar graph as in Figure 41. 
30 ShlITHSONIAS COSTRIBUTIOSS TO BOTASY 

inflorescence in T. excelsa rarely equals the petiole, 

it is usually strongly curved and much shorter than 

the petiole. 

Each primary branch of the inflorescence supports a bicarinate bifid bract (Figure 16~-~) with 

ciliate margins, midway along its peduncle and 

partially included within the tubular primary 

bract. During development of the inflorescence and 

before the flowers are exposed from the primary 

bracts the bifid bract completely encloses the primary branch and its flower buds. Early on the day 

in which anthesis takes place, the primary branch 

including its branchlets elongates rapidly, extending 15 to 20 cm in length during a 10-hour period. 

The branched portion of the primary branch is 

pushed out beyond the bifid bract and becomes 

pendulous (Figure 9~). 

The color of the primary branches and branchlets at flowering is characteristic of the species, 

particularly in T. excelsa. All parts of the branches 

and the flowers of T. excelsa are a bright rosy pink 

or purple, while in T. paruiflora they are creamy 

white to yellowish. In T. radiata and T. morrisii 

they are white, only becoming cream colored or 

yellow with age. 

The primary branches throughout the genus are 

known to be once branched; however, in T. parviflora an occasional plant may produce a primary 

branch that has the lower branches secondarily 

branched. The primary branches of T. pa? vipora 

are typically densely puberulent throughout most 

of its range. Nevertheless at the higher elevations 

puberulence becomes less pronounced and at the 

highest elevations is restricted to protected areas in 

the axils of the branches and in lines on the peduncle. The primary branches of T. radiata, T. 

morrisii, and T. excelsa are entirely glabrous. 

Flowers: The bisexual flowers of the Thrinnx 

alliance are exceptional in the Palmae in having a 

single whorl of perianth, kariable stamen number 

from 5 to 15 or more, and a unicarpellate unilocular gynoecium. The flowers of Thrinax are very 

like those of the rest of the alliance. Except for the 

peculiar stamen character in Hemithrinax there is 

little of practical diagnostic significance in the 

flower. The flowers and associated inflorescence 

. 

. 

. 

. 

. 

. 

. 

FIGURE 19.-Frequency and distribution of pedicel lengths in the three areas of intensive study 

in Jamaica: A, Hollymount Hill; B, Mango Tree Hill; c, Cockpit, Clarendon. Each point on the 

ordinatr represents 10 measurements; pedicel length on abscissa in mm. 
NUMBER 19 31 

parts vary greatly in size and form even within a 

single species. Those of T. paivifiora are the most 

variable among Jamaican species. Thrinax radiata 

flowers are very like the larger T. parviflora flowers. Thrinax excelsa flowers are rather uniform in 

size and form and differ from the aforementioned 

species primarily in the pink perianth and a simple 

horizontal stigmatic opening. 

All Thrinax flowers are to some degree pedicelled, although in T. morrisii the pedicels may be 

very short and disklike. hluch artificial division of 

the genus has resulted from the use of pedicel 

length, its presence or absence, primarily because 

of inaccurate conclusions based on inadequate material. Based partly on this character specimens of 

T. pal-viflora have been described as distinct taxa 

and placed in t~7o different subgenera. Beccari 

(1907, 1933) considered T. tessellata and T. harrisiana to be distinct. He distinguished them from 

T. pamiflora in his keys by their very short pedicels. Bailey (1938) also considered T. tessellain 

and T. harrisiana to be distinct but referred them 

to Sargent’s subgenus “Sessiliflorae” with “sessile” 

flowers. Both names are synonymous with T. parviflom Sw., not of Bailey. Measurements of the variation of pedicel length of plants in the type locality 

of T. tessellata (Hollymount) are recorded in Figures 17 and 19, as locality #lo, where they can 

be compared with the variation throughout the 

species. From a study of a large number of specimens it becomes evident that the flowers are more 

frequently long pedicellate than “sessile.” No inflorescences have been found where conspicuously 

long pedicels are lacking, and none are truly sessile. 

The perianth is a single series in cupular form 

and has a slight basal depression Ivhere it fits over 

the apex of the pedicel (Figure ~OA,B). The upper 

margin is irregularly “6-lobed” or with 6 triangular, acute or attenuate prominences (Figure 

2lc,c,P, and others). According to a study of the 

anatomy of coryphoid palms, hforrow (1 965 ) 

stated that in Thriiiax there are 14 vascular traces 

to the periantli determined at one level as compared to 3 in Hemitlzrinax. Stamen filaments are 

mostly free but are always dilated slightly at the 

base where they are usually very shortly connate 

The material utilized by Morrow in his anatomical studies 

was unfortunately wrongly identified as T. excelsa. This was 

the T. excelsa of Bailey, not Lodd. ex Griseb. It should therefore he called T. mdiata. 

beneath the ovary (Figures ~IB,L; 22~; Z~C,E; 

24G,J,K); although in a key utilizing corollaandroecium structure Morrow (1965:341) stated: 

“C. Filaments free of adnation and connation” by 

which he distinguished Tlzrinax from other members of the alliance which possess, “C. Filaments in 

a ring, becoming free of connation higher up.” The 

stamen filaments of Thrinax may be fused in varying lengths up to the apex (Figure 24~~). One unit 

may in fact appear as a single broad filament with 

two or three anthers affixed (Figure 26). It is to be 

regretted that in Morrow’s discussion of the “Evolution in the Calyx and Corolla of Coryphoid 

Palms,” he neglected any mention of the peculiar 

and unique form exhibited by Thrinax and its 

allies, apart from an exception to his argument 

against a polyphyletic origin of the calyx of coryphoid palms on page 335. The occurrence of a 

perianth in a single whorl must have some evolutionary significance, either as a very primitive condition’ or a highly advanced one in which adnation 

and connation of calyx and corolla parts are carried to the extreme. 

From the earliest description of the genus the 

androecium has been said to have 6 stamens, and 

although flowers are commonly observed with 6 

stamens the most frequently occurring numbers 

are 7 or 8 in T. parvifiora, 7 for T. radiata, and 

FIGURE 20.-Schematic drawings of developing frUit:A, immature fruit on pedicel, longitudinal section; B, base of fruit 

and perianth, nl, testa, B2, pericarp, n3, stamen filament, 

154, perianth; cl, endosperm c2, 3, testa, c4, vacancy by 

shrinking endosperm. 
32 SMITHSOSIAN CONTRIBUTIONS TO BOTANY 

8 or 9 for T. excelsa. Five stamens per flower is by 5 to 10(-15). The mean number of anthers varied 

no means a rare condition and the number of sta- from 6.5 to 8.8 among the 11 collections. These 

mens quite often exceeds 10 or 12. The range of figures are to be compared to 5 to 8 (-10) (y=6.5) 

variation in anther number of 784 flowers of for T. radiata (127 samples) and (6-)7 to 10 (-11) 

T. @rviflora from among 11 different collections is (X=7.5) for T. excelsa (50 samples). 

FIGURE 2l.--Thrinax parvipora, iariahility of Rowers: A-T., Hollymount Hill; H-I, DeLils Backbone; J-P, Cockpit; B, L, filament bases; D, 0, longitudinal section of pistil; c, G, P, perianth; 

N, cross section showing perianth and filaments. 
NUMBER 19 33 

The anthers are basifixed, and although the sacs anthers are always slightly divided or retuse at 

both apex and base. The individual sacs are commonly apiculate and unequal in length. The range 

of variation in anther length of 1107 anthers randomly selected from among 12 different collections 

are normally joined by a very narrow connective 

the condition has been observed where one sac is 

attached only at its apex while the other is affixed 

normally along the length of the filament. The 

& D 

H 

B 

I 

Q J 

N 

FICLRE ZZ.--Thrinnx finrviflora, iariabilit) of flowers: A-G, Long Mountain; H-K, Mango Tree 

Hill; L-N, Palmers Cross; I, F, XI, pistil form; G, s, perianth, basally; K, filaments and perianth 

from above. 
34 ShIITHSONIAS CONTRIBUTIONS TO ROTzlhY 

of T. parviflom is (1.1-)1.2 to 4.0 (-4.2) mm. The The gynoecium is unilocular, “bearing a single 

range of means varied from 1.6 to 3.4 mm. These basal bitegmic ovule. The orientation of the microfigures can be compared to (2.0-)2.2 to 3.4 (-3.6) pyle is slightly oblique but it is more orthotropous 

mm (Xz2.8 mm) for T. ~adiata (199 samples) and than campylotropus” (Morrow, 1965:lOB). “The 

(1.2-)1.4 to 2.0 (-2.3) mm (y=1.6 mm) for T. funicular aril is developed to the same extent in 

excelsa (100 samples). Thrinax as in Coccothrinax and Hemithrinax 

n 

N F-3 U 

C 

H 

FIGURE PJ.--Thrinax mdiata: A, (,-I, variability of flowers; B, base of the ovary in vertical 

section showing ovule; c, base of filaments and perianth; D, stigma; E, filaments; F, branchlet 

and pedicels. 
SUXIBER 19 35 

(1965:llO). The ovary is globose to slightly pyriform, usually abruptly constricted into a short style, 

which flares out into an infundibuliform stigmatic 

region in flowers of T. ~awiflora and T. radiata, and 

is usually quite oblique or sometimes lateral. In T. 

excelsa the stigma appears as a simple conical depression in the apex of the style. The margins of 

the stigmatic region in T. paruipora and T. radiata 

are frequently undulate and ciliate. 

Observations over a period of time on a plant of 

B 

H 

9 

I 

F 

B 

G 

C 

L 

E 

FIGURE 24.-Thrinax excelsa: A, B, flowers at anthesis; c, D, apical portion of branchlet showing 

the relationship of terminal flower and apex: E, shows an apical flower with its subtending 

bract; F, perianth cupule; G, filaments surrounding the base of the ovary, some variously connate; 

H, longitudinal section of pistil showing v-form stigmatic region, and ovule; I, stigmatic region 

in the apex of the style; J, connation of filaments: K, stamen filaments dissected from flower; 

L, base of ovary in cross section, showing ovule and funicular aril; Lr, funicular aril removed 

from ovule. 
36 SMITHSOiiIAN COSTRIBUTIONS TO BOTANY 

T. paruiflora reveal that the stigma is tightly compressed laterally obscuring the stigmatic surface at 

anthesis. Within twelve hours all anthers had dehisced and the released pollen was adhering to all 

surfaces of the inflorescences, but the stigmas were 

still closed. Twenty-four hours following anthesis 

the stigmas were open in the form of a funnel. 

Pollen was still plentiful on the inflorescence 

branches and by shaking the inflorescence a large 

quantity was dislodged. A second plant in the immediate vicinity was at anthesis at the time the 

stigmas were receptive. 

The length of the style-stigma is quite variable 

and although fairly constant among the flowers on 

FIGURE 25.-Immature fruits of Thrinax pamiflora showing 

variation of stigmatic remains; both from the same collection 

a sing1e plant, it varies among the 

plants in a single population. The stigmatic reon the Devils Backbone, Jamaica. mains are most prominent during development of 

FIGURE 26.--Thrinax parviflora: A, abnormal flower with two anthers on a single filament; 

B, seed dissections showing intrusion of the testa (upper row longitudinal and cross sections 

through the embryo, bottom row apical and basal intrusion, left to right respectively); c, D, 

developing fruit exhibiting symptoms of fungal infection. 
NUMBER 19 37 

the fertilized ovary and in the young fruit. Figure 

25 illustrates the variability of the length of the 

stigmatic remains on the young fruit of plants of 

T. paruipora growing side by side on the Devils 

Backbone. 

The ovary enlarges rapidly following anthesis 

and therefore provides a very poor character for 

comparative studies. The surface of the ovary in all 

three Jamaican species is smooth at first but follo~ving fertilization considerable change takes place, 

especially in T. pU7Uifl07”U. As the ovary enlarges, 

the surface rapidly becomes slightly papillate and is 

soon completely covered by minute granulations 

(Figures 25, 26~). 

In a discussion of the nature and evolution of 

the unilocular gynoecium that Rforrow queries as 

“unicarpellate or multicarpellate,” he (1 965) suggests that 

there are at least three possibilities: 

1) The unilocular gynoecium is a single carpel, produced 

from ontogenetic or phylogenetic abortion of two other 

carpels. 

2) The unilocular gynoecium is a single carpel but ha? 

captured the vascular supply of two carpels which abort, 

3) The unilocular gynoeciuni is composed of three carpels, 

which grew together in such a manner as not to be recognizable. 

He further suggested that “first . . . the unilocular forms have skipped a developmental step; and 

second, the development of the ovary occurs prior 

to anthesis.” 

Morrow (1965:355) stated that, “Normally unilocular species (Thrinnx et al.) have been seen 

with 2 locules,” and in this connection it seems 

appropriate to describe a curious phenomenon obFIGURE Z’i.-.Anomalous flowers of Thi itznx p1n1iflorn; apical 

flowers exhibiting partial fusion of parts. Explanation in the 

text. 

served in a number of specimens of Thrinnx pmviporn. A herbarium specimen at the Institute of 

Jamaica had on it a flower that seemed to be bicarpellate, but since soaking and dissection would 

have destroyed the flower, investigation was delayed 

until fresh material could be obtained. Fresh flowers at anthesis were collected on Portland Ridge, 

Jamaica, in which apparent fusion of flowers was 

in process. Figure 27~ shows the apex of a racliilla 

upon which the apical flower possessed two distinct 

carpels and nearly double the normal number of 

stamens. The perianth formed a single 12-lobed 

whorl surrounding tlie base of the androecium. 

The possible explanation became apparent when 

the flower illustrated in Figure 27A-C was studied 

and dissected. On one side the perianth, although 

partly fused at the base, turned in apically and 

continued partly between the two carpels (Figure 

25B). On the opposite side the perianth was a 

continuous “normal appearing” cupule enclosing 

both halves of the “flower” (Figure 27A). Two of 

the stamen filaments obviously originated between 

the two carpels. The arrangement of androecia and 

gynoecia diagrammed in Figure 2ic clearly indicates that two flowers are partially fused on the 

apex of the rachilla. Fusion of the perianth is onl) 

partial1.y complete. Other flowers have been observed in which the two carpels are apparently 

situated side by side without stamen filaments 

between them and with tlie perianth completely 

enclosing the base as a single multilobed unit. A 

situation of this sort could possibly explain the 

2-locular ovary cited by Morrow. 

Fruit: The fully developed but not fully mature 

fruit of T. pa~ipora may exhibit any one of several different characters. Fruit not infected or damaged by fungus attack (see section on Phytomorphosis) may be granulate, densely papillate, or even 

tuberculate and they often become scurfy as the 

hiit matures. Young fruit of T. radialn and T. excelsn are generally smooth to slightly pustulate or 

with widely spaced papillae. F~illy mature fruits of 

all four species are smooth and white or creamy 

white. 

The seed of Thrinax is subglobose with a subapical embryo and is intruded partly or completely 

by the testa. The seeds of all three Jamaican species 

are completely intruded from base to apex. The 

seeds of T. mowisii differ in that the seeds are not 

completely intruded by the testa, rather the testa 
38 SVITHSONIAS COX TRIBUTIONS I0 BO I'ASY 

intrudes little more than halfway from base to 

apex. In fruit not quite fully developed (Figure 

~OB), the endosperm (cl) is rubbery and the intrusion of testa is easily observed as a dark fleshy 

tissue (c2) continuous with the very thin testa 

(c3) surrounding the endosperm. In longitudinal 

section the drying endosperm has pulled away 

from the central intrusion of testa (Figure 20c4; 

see also Figure 26~). 

GERMINATION OF SEEDs.-The mode of germination of the seeds of Thiinax is similar to that of 

Phoenix as described by Gatin (1906) and Tomlinson (1960). The cotyledonary haustorium remains 

in the endosperm and the cotyledonary petiole 

(Figure 16~~) by elongation pushes the radical out 

and down, burying the plumule and cotyledonary 

sheath a few centimeters into the substrate. The 

plumule then emerges through a split in the upper 

surface of the cotyledonary petiole. 

Of interest, taxonomically, is the fact that in 

T. excelsa and T. moiyisii the cotyledonary sheath 

is pubescent throughout but that of T. pawifloin 

is pubescent for only halt its length, the lower 

portion remaining naked. 

The first postcotyledonary leaf is tubular, sheathlike and bladeless, and usually pointed at the apex. 

The first seedling leaf, termed an eopliyll by Tomlinson (1960), has a narrowly lanceolate green 

blade. Several successive seedling leaves are lanceolate, but leaves with three, and eventually more, 

segments are soon produced. The leaves produced 

henceforth become more and more complex as they 

appear with increasing numbers of segments. 

POLLFN.-T~Y~R~X pollen is pale cream colored 

to white, elliptic to broadly elliptic in outline, and 

monosulcate. The exine, when viewed by means 

of the light microscope, appears to be fairly uniformly psilate-foveolate among the four species; 

however, photographic studies by means of the 

scanning electron microscope clearly suggest the 

possibility of distinguishing between species by 

means of pollen-exine morphology. Further studies 

FIGURE 28.-Portion of fruiting inflorescence of Thrinax'nwrrisii; fruit about natural size; note 

the bumplike pedicels. 
SUhlBER 19 

of pollen from the extremes of the ranges and ecologies of the four species and their subspecies would 

be necessary in order to establish whether or not the 

types illustrated here are in fact really different or 

if they merely represent isolated parts of a range 

of variation. Certainly the character of the exine of 

T. paruiflora is somewhat distinct from that of 

T. excelsn, and the exine morphology of T. radiatn 

and T. ~noi~i~ii, while differing somewhat from the 

others, appears to be simply variations on a similar 

theme. 

Anatomy 

In his studies on the anatomy of palms, Tomlinson (1961:3) was correct in his observation that 

“specific identifications have never been very reliaFIGURE 29.-Scanning electron micrographs of Thrinax pollen enlarged about 2600 times: A, T. 

parvipora; B, T. mdinfn; c, T. excelsn; D, T. morrisii. (Photographs courtesy of the SEM 

laboratory staff, from samples prepared bj- the Botany Palyology Laborator) at Smithsonian 

Institution.) 
40 5>51THSONIAN CON1 RIBUTIOSS TO HOTAUY 

FIGURE 30.-Scanning electron micrographs of Thritiax pollen magnified about 10,000 times. 

A, T. parviflora; B, T. radiata; c, T. excelsa; D, T. morrisii. Xote how different the surface 

pattern appears under the much greater magnification. 
SUMBER 19 41 

ble.” But he states: “In many genera this is no 

disadvantage since interspecific differences are often 

only quantitative and are obscured by anatomical 

variation within a single species.” This statement 

may be true for other palms but in the genus 

Thrinax, once the taxonomy is worked out, certain 

anatomical characters follow the same pattern as 

the key morphological characters. It is now possible to identify accurately each species of the genus 

simply by comparing the anatomical characters of 

the lamina with the following key or the accompanying illustrations. 

Anatomical Key to the Species of Thrinax 

Using Laminar Characters 

I. Laminar cross section composed almost entirely of palisade cells: stomata deeply sunken: 

abaxial outer epidermal cell walls greatly thickened, surface very irregular . . T. morrisii 

1. Laminar cross section composed of either distinct layers of palisade and mesophyll, or palisade 

cells few and scattered; stomata not sunken: abaxial epidermal cell walls not greatly 

thickened nor is the surface highly irregular. 

2. Palisade and mesophyll layers quite distinct; hails when present large and cornplex with 

numerous surface cells in cross section. 

3. Stomate guard cells in cross section, hooklike in appearance . . , , T. radiata 

3. Stomate guard cells in cross section, not at all hooklike in appearance T. excelsa 

2. Palisade cells absent or rather uncommon and widely scattered if present; hairs when 

present, small and with few surface cells; stomate guard cells, in cross section hooklike 

in appearance 

hIATERIAL AND h!fETHODS.-In most cases Samples 

of 2 sq cm each of dry herbarium material were 

selected and soaked overnight in aerosol (Ayensu, 

196‘7). Thin sections were then made by hand using 

a sharp razor blade with the specimen supported by 

elderberry pith. The sections were then stained 

using a 0.05 percent solution of toluidine blue in 

0.15 R/I phosphate buffer for a few seconds and 

mounted in ethylene glycol under glass cover 

slips. Neither soaking in sodium hypochlorite solution nor heating in hydrochloric acid seemed to 

make the material easier to section. The material 

to be sectioned was selected from the midportion 

of leaf segments, about halfway bet.rveen apex and 

hastula, between the major veins. 

The following account of the anatomy of the 

lamina of Thrinax is based in part on a treatment 

of the genus by P. B. Tomlinson (1961), but it 

has been modified significantly by more recent personal observations. Tomlinson’s treatment was unfortunately based on a mixture of both Coccothrinax and ThTinax, closely allied but distinct genera. 

He (p. 296) concluded that 

from the material . . . examined, although some of it has 

not had a reliable name and may have been confused Hith 

Coccothrinax, there appears to be considerable \ariation in 

the anatomy of the lamina, particulaily in the stiucture and 

distribution of the hairs and the disttibution of the ceins 

~ 

T. pamiflora 

and fibrous strands, Since the taxonomy of Thrinax and 

related genera seems to be rather confused, little reliance 

can be placed on the anatomical information which has SO 

far been recorded until a detailed survey can be made upon 

a large number of species from accurately established sources. 

The elements that do not agree with observations 

on verified Thyinax materials have been removed, 

and in addition to my own new observations those 

that do apply to the genus Thyinax have been 

retained. 

LAMINA o.--Hnins frequent in abaxial costal regions, each with sunken, elliptical, sclerotic, multicellular bases. Ciilicle thick, Epidermis wholly cutinized, outer wall somewhat thickened. Adaxial 

epiderniis fairly uniform, costal regions tlifferentiated only above largest veins, cells rather variable, mostly more or less cubical or slightly longitudinally extended, walls not sinuous. Xbaxial 

epidermis differentiated into narrow costal and 

wider intercostal regions. Costal cells rectangular, 

longitudinally extended, narrow, shallow; intercostal cells less regular, shorter, wider, deeper, 

and slightly papillose. Stomata restricted to 

abaxial intercostal regions, those of both T. ra- 

’ Grateful appreciation i? extended to Mrs. Li5a Keys, 

graduate Ttudent at the CniLersity of \faswchusetts, for her 

freelt \olunteered help in the preparation of materials and 

hand sections used in the laminar anatomy. 
42 ShIITHSOSIAS CONTRIBLTIOSS TO BOTASY 

FICCRE 31.-Camera lucida drawings of Thriiznx leaf sections: A, T. parviflorn (Read 1736, 

Devils Backbone); B, T. escelsn (Read 193Gb, John Crow Mountains); c, T. radiata (Read 1862, 

Morant Point); D, T. morrisii (Read 798, Grassy Key, Fla.). 
KUMBER 19 43 

diata and T. parvipora similar in cross section as 

in Figure 31~,c, while T. excelsa and T. morrisii 

share similar guard-cell types which differ from the 

other two species (Figure 31n,~). Hypodermis 1- to 

2-layered below each surface but adaxial liypodermis mostly 2-layered; cellfiles often replaced by 

fibers. Adaxial cells rectangular, longitudinally extended. Abaxial cells more cubical, irregular in 

intercostal regions. Chlorenchymn with a fairly distinct 2- to 3-layered adaxial palisade (except T. 

parvipora which has only widely scattered infrequent palisade cells, the chlorencliyma being primarily composed of mesophyll). TIirinax morrisii 

is distinctive in having the chlorencliyma composed 

almost entirely of palisade cells. Xbaxial mesopliyll 

cells more or less isodiametric, compact. Fibers frequent, mostly in strands below each surface. Adaxial strands irregular, with 1-21 (rarely more) fibers 

per strand irregularly intruding the chlorenchyma, 

these adjacent to the epidermis or separated from 

the epidermis by a layer of small hypodermal cells. 

Abaxial strands with fewer fibers, sometimes cylindrical, mostly adjacent to adaxial epidermis. Veiny 

mostly in abaxial mesophyll or equidistant from 

either surface. Outer parenchymatous sheath complete around, or interrupted below small veins, 

always interrupted both above and below large 

veins; sheath-cells cubical, often containing chloroplasts. Inner sclerotic sheath completely fibrous 

around large veins, usually including sclerotic 

parenchyma adjacent xylem of small veins. Phloem 

of large veins not subdivided, rarely slightly sclerotic. Transverse com missures usually in abaxial 

mesophyll, rather infrequent, wide. Ribs most 

prominent adaxially in proximal part of lamina. 

Surface layers similar to those of lamina, with few 

small hypodermal fibrous strands. Central ground 

parenchyma containing several vascular bundles: 

those in adaxial ribs with well-developed, somewhat confluent, fibrous sheaths; those in abaxial 

ribs more or less surrounded by a common sclerotic cylinder. Expansion cells in bands, including 

fibrous strands, within each fold of the lamina. 

These studies have provided the only positive 

means of identifying Thrinax radiata with living 

taxa. 

Leaf Axis: Epidermis with more or less cubical 

cells; walls thickened, cutinized. Stomata occasional, 

slightly sunken. Hypodermis I-layered, inconspicuous, sometimes slightly lignified. Peripheral chlorenchyma indistinct. Fibrous bundles occasional in 

chlorenchyma. Vascular biindles uniformly scattered, not congested at the periphery; each with a 

complete fibrous sheath, usually including 2 wide 

metaxylem vessels and an undivided, not sclerotic, 

phloem strand. 

Cell Inclusions: Stegmata of leaf in short, often 

continuous, files mostly adjacent to vascular fibers. 

Silica bodies spherical, spinulose, diameter 12 

microns; basal wall of silica cell slightly thickened. 

Enlarged cells filled with raphid bundles are fairly 

common between the smaller veins. 

T’ascular Elements: Vessels: elements of leaf with 

sclariform perforation plates on oblique end walls. 

Sieue tzibes: elements of leaf with compound sieve 

plates on more or less transverse end walls. It was 

noted by Partliasarathy (1968) that the Thrinax 

alliance and Licztala are exceptional among coryplioid palms in possessing more arecoid than typically coryphoid sieve plates. Furthermore, he stated 

that Thrinax in common with other closely allied 

genera is also set apart from most coryphoid palms 

by having but a single phloem strand, and sclerotic 

parenchyma cells in the metaphloem of many vascular bundles. 

Literntiire: The greatest criticism concerning 

studies by earlier workers is that most of the material was Lunreliablj identified, as mentioned by 

Tomlinson (1961). Furthermore the material was 

either obtained from botanical gardens which are 

questionably reliable, unless vouchered materials 

are available at the institution, or the materials 

were obtained from herbarium specimens Tvitliout 

citation of specimen numbers or collector. Thus 

the unvouchered materials used by past workers 

cannot now be identified with certainty. 

Tomlinson (1961:296) cited as his material, ‘IT. 

argenten Lodd. -Kew. Leaf,” which is probably a 

Coccothrinax; and “T. tessellata Becc. Jamaica. 

Leaf,” which name is now in synonymy of Thrinax 

parviflora Sw. Drabble (1904) treated T. excelsn 

Lodd. and T. pa?vipora Sw., the former name having been applied to T. radiata in Jamaica and the 

latter to T. radiata in Florida. Gillain (1900) treated T. argentea Lodd. and T. gTaminifolia IVendl., 

the first a Coccothrinax and the second a nomen 

incertum. Jost (1887) and Zawada (1890) simply 

cited “Tlirinax sp.” And of the nine taxa attributed 

to Thrinax in the study by Pfister (1892) only “T. 

exceZsn Lodd.” could be a Thrinax but certainly 
44 SMITHSONIAN COK?'RIBUTIONS TO BOTANS 

not of that species. Rudolph (1911) and Solereder 

and Meyer (1928) worked only with species of 

Coccothrinax. 

Cytology 10 

The species of Thiinax in Jamaica, in addition 

to many other similarities already mentioned, have 

a chromosome complement similar in number antl 

morphology to other members of the alliance. The 

results of the present study when compared with 

previous work (Read, 1963, 1964, 1965a, b) lead 

to the conclusion that, as far as can be determined, 

it is not pissible to distinguish between genera ot 

tlie Thrinax alliance by means of their chromosome karyotjpes. The relatively large size, 1-3.0 

(-3.5) microns in length, of the cliromosomes places 

Thrinax, together with its closest allies, in a group 

of palm genera having chromosomes of a similar 

size but which differ primarily in having a 2- 

whorled perianth and a 1- to 3-carpellate ovary 

(i.e,, Sclzippia, Ciyosophila, Trithinax, and ChelyOCG~~IIS). Except for the genera just mentioned antl 

several genera of dioecious palms, which also have 

large chromosomes, all other coryphoid palms 

studied thus far have mostly very small chromosomes, 0.5 to 1.5 (-2.0) microns long. 

The karyotype for each species exhibits an almost complete gradation of sizes from smallest to 

largest with some recognizable differences in morphology. With such small chromosomes, however, 

and with the present technique it has proved unsatisfactory to attempt a classification of size or 

morphological groupings. Chromosome size may 

vary considerably among the preparations of a 

single species or individual depending on the timing of pretreatments or fixation and especially tlie 

degree of squashing. And although certain cliromosomes are recognizable as having subterminal, submedian or median constrictions, it is extremely 

difficult to differentiate between real and apparent 

differences. For example with such small cliromosomes, as so often happens, they do not allvays lie 

flat or parallel with the level of resolution. It is 

then possible to misinterpret a chromosome which 

1°From work related to a project supported by National 

Science Foundation grants G-18770 and extension GB-13.54. 

IVhile in Jamaica the Botany Department of the I:.IV.I. acquired phase-contrast attachment5 especially for use by the 

author in his research on palm cytology. 

may have part of its arms bent down or under; 

thus a submedian or subterminal primary constriction may appear as a median or submedian respectively. An ideal preparation would require squashing to less than 0.5 micron in order to flatten the 

chromosomes sufficiently. This has not been possible because of the presence of the pollen grains 

in the preparation. 

MATERIAL AND METHODS.-A~~ material used in tlie 

present study was collected from wild plants in 

the field in Jamaica. 

4 detailed description ot the technique has already been published (Read, 1965), therefore only 

a brief review need be given here. Portions of inflorescence were collected at antliesis or as soon 

before as possible. The pollen was collected by 

allowing it to shed on a piece of paper in a draft 

free room. It was then stored in gelatin capsules 

and placed in an airtight container with dry silica 

gel and a color indicator, at room temperature 

(about 26°C). It was necessary at times to dissect 

the unopened anthers from the flowers and permit them to dry in the gelatin capsules and silica 

gel. It was important not to store more pollen in a 

capsule than would effectively coat the walls when 

dry, otherwise the possibility of fungal and bacterial contamination became serious. 

Pollen was sown on a nutrient medium (100 ppm 

H,BO, in water; 0.02% colchicine in distilled 

water; 10% lactose or sucrose and 10% gelatin) for 

tlie study of pollen-tube mitosis. After heating 

medium slightly it was applied to cover glasses by 

means of a small cotton swab. Tlie pollen was 

dusted lightly over the surface of the dry medium 

and the cover glass then overturned onto a Van 

Tiegliem cell lined with moist absorbent paper. ,4n 

improved method was to place the rings that form 

tlie Van Tieghem cells directly on a layer of moist 

absorbent paper lining the bottom of a plastic 

tray. After the prepared cover glasses were in place 

the container was closed to prevent drying. Tlie 

tray was maintained at room temperature (about 

26°C) and germination was usually found to have 

proceeded sufficiently within 8 to 10 hours. 

When examination of sample slides indicated 

that mitosis was in process, the cover glasses were 

stained with acetocarmine and made permanent by 

the vapor transfer method. All counts and drawings 

Tvere made on freshly prepared slides. The tapping 

and differential squashing necessary to produce the 
X'UJIBER 19 

FIGURE 32.-Photomicrographs of the chromosomes of species of Thritiax at pollen tube mitosis: 

A, R, T. pnrviflora, Read 1657; c, T. pnrr?iporn, Read 1675~; D, T. excelsn, Read 1625. (X ca. 2500.) 

45 
46 SMITHSONIAS CONTRIBUTIONS TO BOTASY 

FIGURE 33.-Photomicrographs of the chromosomes of species of Thyinax at pollen tube mitosis: 

A, B, T. radiata, Read 1671; c, D, T. movjsii, Read 143ia. (X ca. 2500.) Note the chromosomes 

obviously stiH within the developing pollen tube in Figures B, C. 
KUJIBER 19 47 

best figures was not possible after a few hours. 

Drawings were made with the aid of a camera 

lucida, and the photographs were made on 35 mm 

film either in black and white or color (Kodachrome 11). The use of phase-contrast aided immeasurably in distinguishing between closely situated chromosomes and also produced photographs 

of better quality. 

Before the present study was undertaken, reports 

of chromosome numbers in Thrinax were already 

in the literature; however, as a result of the present 

revision of the nomenclature among the Jamaican 

taxa, it is necessary to revise the names cited for 

the species for which chromosome numbers have 

been reported. Thrinax excelsa as reported by 

Venkatasubban (1945) and Read (1963) should be 

named T. iadiata. Thrinax parvifloia and T. floridana as reported by Read (1964, 1965a respectively) should likewise be named T. mdiata. Thrinax 

miciocarpa as reported by Read (1963, 1964, 1965a) 

should be named T. morrisii. 

Thrinax radiata has been reexamined using 

native material from its natural habitat. Authentic 

T. excelsa also lias been studied from material 

collected in the field. It was particularly interesting, 

early in the research, to compare the chromosomes 

of T. parviflora from plants growing in the extreme 

climates in which the two biotypes occurs. The 

chromosome number in each case lias been determined to be n=18, agreeing with all other Cory 

phoid palms studied to the present. Idiograms of 

each species in Jamaica are illustrated in Figure 34. 

Thrinax pnrviflora from a lowland habitat at 

Cockpit, Clarendon, is represented by a, b, and the 

high elevation phenotype from plants on the Devils 

Backbone is represented by c, d, e. Thrinax ?-adinfa 

is represented by idiograms f, g, and T. excelsa by 

idiograms h, i. 

FIGURE 34.-Idiograms of Thrinax showing their cornparati\ e karyot) pes. a, b, T. parvipora, 

Read 167%; c-e, T. patvzflota, Read 1736; f, g, T. radmta, Read 1671; h, 2, T. eucelsa, Read 

1625. 
48 SMITHSONIAS CONTRIBUTIONS TO BOTAKY 

Phytomorphosis and Zoomorphosis in 

Thrinax parviflora 

The specific epithet “tessellata” was applied by 

Beccari (1907:Zil) to a specimen from Hollymount 

at the upper elevations on Mt. Diablo. The name 

was given in allusion to the fruit which Beccari 

described as having the “epicarpio distincte suberosotessellato,” a condition common in the cool 

moist environments where a fungus infection radically alters the exocarp of the fruit producing the 

condition shown in Figure 26~. The fruit can become infected at almost any stage of development. 

Figure 26~ shows two stages in the development of 

the fungiis on young fruits. The fruit on the right 

has a small area where the epidermis has only 

begun to erupt as a result of the fungal activity. 

The fruit on the left has no trace of epidermis 

remaining as in Figure 26c. Fruits exhibiting both 

partial and complete alteration of the epidermis 

are part of the isotype of T. tessellata, herein treated as synonymous with T. parviporcr. The fungus, 

although observed in situ, has not yet been isolated 

and identified. 

In the same environment where fungal damage 

is common on tlie fruit, the branches of tlie inflorescence also undergo a dramatic change. Extensive grazing by caterpillars causes considerable 

damage to the epidermis and outer tissues of the 

branches (Figure 35). So extensive is the damage in 

some areas, it is seldom possible to find healthy or 

uninutilated epidermal tissue anywhere on the inflorescence branches. The grazing creates a distinctive pattern of trenches, exposing the fibrovascular 

bundles, intersected with narrow ridges of ungrazed 

tissue in Figure 35B. At the lower elevations only 

occasional damage by larval grazing is encountered 

on specimens and this is usually of minor importance (Figure 35A). At the higher elevations, however, it is seldom possible to determine the nature 

of the epidermis (e.g., degree of puberulence), or 

for that matter even to find ungrazed epidermis at 

all on fruiting material. 

The apex of tlie petiole in the region of the 

abaxial hastula and infrequently even the adaxial 

hastula are often grazed extensively. Often the 

abaxial liastular region of the youngest leaf on a 

plant is completely grazed of epidermal tissue exposing a network of fibrovascular bundles. 

Breeding System 

The breeding system is very difficult to understand completely, primarily as a result of the difficulties of observing anthesis in the field. Individual 

plants may bear as many as 6 to 10 inflorescences 

each year and at one time. The most conspicuous 

feature of an inflorescence at anthesis is the predominance of anthers. Lacking conspicuous and 

enclosing perianth parts, tlie anthers are exposed 

immediately as the primary branches are extended 

beyond the primary bracts. The anthers in turn 

obscure the pistil. Each inflorescence may have 

between 7 and 21 primary branches. These decrease in size and the number of secondary branches 

successively toward the apex. Those at the apex 

may have only 6 to 10 secondary branches. The 

primary branches below the apex may possess from 

I7 to 47 secondary branches and each of these may 

possible for each plant to prOdLlce between 100,000 

and 300,000 flowers over a 24-hour period. ConsidFIGURE 35-Grazing by caterpillars has pioduced vai)ing have fro111 about 40 to 115 flowers. Therefore it is 

amounts of damage to the infloiescence branches of Tflit?lax 

parzupoia. Vasculai bundles ale exposed in ’‘13.’’ 
SUXIBER 19 49 

ering also that each flower may possess froin 5 to 15 

stamens, each of which produces an abundance of 

light dry pollen, it can easily be seen that the production of pollen by a single plant is phenomenal 

indeed. The anthers dehisce almost immediately 

as the sun rises and atmospheric moisture decreases. 

Normally all parts of the inflorescence are covered with scattered pollen very shortly after anthesis. When an inflorescence was permitted to reach 

anthesis overnight in a closed office, all surhces, 

books, and objects in tlie room were visibly coated 

with pollen within an hour. 

The light, dry pollen of Thi-inax is conceivably 

carried over very long distances by the wind and 

has been determined to remain viable for periods 

up to 3 or 4 months at room temperature (about 

26°C). Pollen of T. fiarvifloia collected on 12 January 1967 was maintained dry in gelatin capsules 

that were kept in containers of silica gel with a 

color indicator at room temperature. Samples of 

this pollen were sown and germinated on the medium used in the cytological studies at intervals 

over a 4-month period. Pollen viability was excellent at first (between 70 and 80 percent) on 15 

January. It dropped to 41 percent by 9 February, 

and on 27 February had further dropped to 37 

percent. On 1 April viability was only 1 percent. 

It is conceivable then, considering the great quantity of pollen produced by a single plant at one 

time, that crossing need not be a rare occurrence. 

4n attempt was made to test inhibition to selfing. 

Pollen froin two different plants was to be placed 

on the stigmas of emasculated flowers of one 01 the 

plants. A difference in the rate of pollen germination (determined by fixing and staining an hour 

or so after pollination) favoring the outcrossed 

flowers would indicate a resistance to selfing. If 

this were the case, pollen from nearby plants 

would conceivably be able to germinate and coinpete rvith the mass of pollen from tlie flower’s oivn 

anthers. 

Attempts at emasculation of flowers on fully 

developed inflorescences in the field proved futile. 

Within seconds following removal of the enclosing 

bracts the anthers clehisced and scattered pollen 

over the pistils. Further attempts were made on 

inflorescences removed and placed in containers of 

water in the laboratory. It was possible to remove 

the unopened anthers by spraying thein with water. 

It was observed, however, that pollination was effectively prevented by the lateral compression of 

the stigmatic surfaces. Before pollinaton could be 

achieved with certainty tlie flowers fell without 

having exposed their stigmatic surfaces. 

Other attempts were made using inflorescences 

still attached to the crown of a plant which was 

cut at the apex of the caudex and removed to the 

laboratory. hIost of the leaves were removed and 

the cut portion was placed in a container of water. 

Several fully developed inflorescences proceeded to 

reach anthesis during the following night in the 

laboratory, but again the flolvers fell without having exposed their stigmatic surfaces. 

Further observations on plants in the field confirmed that tlie stigmas are tightly compressed at 

anthesis and follow roughly the following schedule: 

FIGURE 3G.-Flower of Thrinnx pari1i//orn. Photographed with 

a Contaflex camera, hand held on a binocular-dissecting 

microscope and using Kodachrome I1 film exposed for 10 

seconds. Kote the form of the stigmatic region. 
50 S\fITHSOhIIAN COh 1 RIBUTIOUS TO BOTANY 

21 Sept. 7:30 p.hi. 

22 Sept. 8:OO A.M. 

A few rachillae and flowers exposed. 

All rachillae and flowers exposed; flowers 

creamy-white including ovary; anthers 

dehisced; stigmas tightly compressed. 

22 Sept. 8:OO P.M. Pollen covering all infloyescence parts; 

stigmas still compressed. 

23 Sept. 9:30 A.M. Ovary yellow, conspicuous; quantities of 

pollen still present; stigmas open, 

funnellike. 

That this is not always the situation is borne out 

by pickled material in which the anthers ale not 

fully tlehisced while the stigma is fully open and 

by the photograph (Figure 36) showing a flower at 

anthesis with its stigma fully open and apparently 

receptive. 

The fact that the stigmatic surtaces are often 

closed during anthesis, effectively preventing selfing, 

permits a period during lvhich pollen from surrounding plants can mix either in the air or on 

the inflorescence before receptivity of the stigma 

occurs. Thus although the chances for selfing are 

far greater, outcrossing is not ruled out altogether. 

Success of the species seems, however, to depend on 

the fact that, lacking pollen from another population or another plant, seed production is assured 

in quantity by selfing, as evidenced by the excellent 

fruit production of solitary individuals in the field 

or in cultivation. 

Flowering in Jamaica: In January 1966, several 

plants of T. parvifloi-a on Mango Tree Hill, in 

Trelawny, were observed to have inflorescences 

exposed in bud for about 20 cm. Subsequent and 

frequent trips to the area found the inflorescence 

unchanged until 14 May when the same inflorescences were at a stage one or two days past anthesis. At Cockpit and Palmers Cross in Clarendon the 

entire population was at full anthesis on 9 June, 

while all the plants on Long Mountain, St. Andrew, 

had flowered a month earlier on 8 May. 

It was observed, in 1966, that most inflorescences 

of a single plant reached anthesis within a 48-hour 

period. This is notable considering that the 4 to 6 

or more inflorescences reaching anthesis at the same 

time had developed in the axils of successively produced leaves over a 12-month period two seasons 

earlier. Apparently each solitary inflorescence produced within each leaf axil remains at a particular 

stage until several reach the same stage. They then 

proceed development together and reach anthesis 

at the same time. Each plant presumably has 3 

seasons of inflorescence production at any one time. 

The 3 or more older lea\es subtend 3 or more spent 

inflorescences; the 3 or more younger leaves subtend inflorescences at or past anthesis, or in fruit; 

and, apically, 3 or more youngest leaves subtend 

resting or developing immature inflorescences. 

Each season a select number reaches anthesis at 

once, during which time the next season’s inflorescences will be reaching a certain stage of equal 

development. 

In Table 1 the localities, within each subspecies 

grouping, are arranged in descending elevation from 

the top toward the bottom. It can be Seen that in 

any one year, widely separated populations flo~vTABLF 1.-Flowering and fririting dates for Thrinax 

parviflora arranged by phenotypic expression (localities 27-30 represent subspecies parvipora; 33-29 

represent subspecies pubertila) 

I.ocality 

nti m her 

27 

10 

8 

I 

5 

32 

31 

30 

33 

2 

14b 

38 

34 

3 

36 

17 

40 

26 

42 

21 

4 

22 

24 

29 

An thesis 

Jan 1967 

Mar 1967 

Jan 1967 

Jan 1967 

Jan 1960 

Jan 1967 

Nov 1964 

May 1966 

Jul 1967 

May 1966 

Jul 1967 

Apr 1963 

May 1966 

Jun 1967 

Sep 1967 

May 1966 

May 1966 

May 1966 

Jun 1966 

Jim 1966 

Jun 1966 

Jim 1967 

Immature 

fruit 

Feb 1955 

Mar 1967 

Jan 1958 

Jan 1956 

Apr 1955 

Mar 1960 

Aug 1955 

Jill 1966 

Feb 1967 

Aug 1966 

Mature 

fruit 

Jun 1966 

4pr 1966 

May 1966 

Nov 1966 

Nov 1965 

Nov 1955 

Oct 1955 

Aug 1955 

Nov 1965 

Nov 1955 

Nov 1965 
SUhIBER 19 51 

ered several weeks to a month apart. This was especially true in 1966. 

A plant removed from a hill near Silver Spring, 

Hanover, and planted in the palm collection at 

hlona, produced an inflorescence, antl reached anthesis on 26 May, but the pollen was sterile. Additional plants were collected at Cliarlton, TVintlsor 

Cave, and Negril Hill on 4, 5, and 6 June respectively. These Jvere a week or more past anthesis, 

when collected, providing some overlap in flowering among widely spaced populations. Nearly all 

populations of tlie warm, dry, lower elevations 

leached anthesis between 8 hlay antl 9 June 1966. 

During the first half of 1966, no plants \\‘ere found 

at antliesis or even postanthesis anywhere in the 

higher elevations. The presence of mature fruit on 

29 June at Hollymount Hill suggested that the 

plants may have bloomed during tlie winter. 

In 1967 several individuals from throughout the 

higher elevations were collected at or near antliesis 

between January and March. Flowering and seed 

production must be very irregular and rarely plentiful among tlie plants at the higher elevations, 

for after having collected tlie fev available inflorescences for herbarium specimens antl stud), no fruiting specimens have since been found among tlie 

thousands of plants observed. In January on tlie 

Devils Backbone one of the plants Tvitli fully developed inflorescences was cut below the crown 

and removed to the laboratory. At 9:00 P.M. on 

12 January not one flower was exposed, but by 

8:OO the following morning all piiinai) branches 

were fully exposed and all flou ers were shedding 

pollen. 

Although most of tlie lowland plants have been 

observed to flower during the summer months, a 

single plant of T. paivipoin near Portland Point 

was found at postanthesis in Febiuary 1967. It is 

not known if fruit set as a result, because no fruit 

was found later in the year. 

TVidespread drought and widely scattered, irregular, late, and below normal rainfall in 1967 no 

doubt had a strong effect on the flowering of 

Thyinax paiviporn, because the pattern of flowering at the lower elevations in 1967 was markedly 

different from that described for 1966. A trip to 

hfango Tree Hill in late May, where all plants 

hatl finished bloom by the same (late in 1966, 

yielded not a single inflorescence. Kone were exposed for more than a few centimeters. Two plants 

on Long hlountain, which flowered in early May 

in 1966, flowered on 22 and 23 June 1967. Several 

other plants on Long Mountain hatl inflorescences 

exposed, but they did not reach anthesis until late 

September, several weeks following a period of 

heavy rain which broke tlie 8-niontli drought. 

At Cockpit and Palmers Cross, Clarentlon, not 

one inflorescence was observed on 24 June 196i 

when nearly every plant in the Portland Ridge 

area, a few miles to the south, was at full antliesis. 

Genetic exchange between distant populations of 

T. pavuifloia by means ol pollen exchange is probably very low. Since nearly all plants in a popiilation shed their pollen during a 48-liour period, and 

since populations widely removed from one another 

may flower a week or more apt, it is unlikely that 

pollen from one population can be cari ied through 

wind and rain and still be able to compete a -tveek 

later with the greater mass of pollen already available on an inflorescence in another population. 

Except for this unlikely but possible exchange of 

pollen, genetic exchange between local populations 

niost likely results from the indiscriminate distribution of seed by birds and the resulting plants 

crossing with their neighbors in tlie new locality. 

Plants of T. Iadiatn have been observed in flower 

or fruit tliroiighout the year. Most of the plants in 

a given population are usually at the same stage of 

bloom or fruit, but there seems to be no definite 

season. Thrinax excelsa has been observed in flower 

from .4pril to September, and fruit has been collected from July through September. 

Seed Divt~ibzctioiz: Doves and pigeons are common throughout the range of Thyinax in Tainaica, 

antl have been reported by the country people as 

niost plentiful when the “thatch” is in fruit. It 

was said of tlie hills near Silver Spring, Hanovel, 

that, “Bald Plates” [sic] are seen in flocks feeding 

on the thatch “peas.” At the time of my visit to tlie 

‘ires, the palms were not in fruit and no “Bald 

Plates” were in evidence. There are eleven species 

of dokes or pigeons indigenous to Jamaica and the 

Baldpate or TYliite Crowned Pigeon is coinnion 

throughout the distribution range of T. Tadiota 

in the northern Caribbean. Several of the others 

are common to Jamaica and neighboring islands 

but the Baldpate is said to move freely among the 

islands (Bond, 1961). 
52 SSIITHSOXIAN COSTRIBUTIONS TO BOT’ASY 

Variation of Thrinax parvijlora plants, the true extent of genetic differentiation 

Thyinax parviflora is a highly variable and polymorphic species and occurs over an equally variable 

and complex system of environments from near sea 

level to about 914 in (3000 ft) elevation. Considerable effort has been expended in attempting to 

correlate variability of phenotype with environment. Lacking experimental evidence, holvever, of 

any genetic bases for the variation, it is not possible 

to do more than describe the range of variation in 

the various environmental zones. Until such a time 

as plants from the different areas are grown under 

identical conditions and/or with reciprocal transcannot be known. 

The extent of variability can be and has been 

measured by field studies on plants in 42 localities 

throughout the entire range of distribution of the 

species, and in nearly every ecological situation 

over a 2-year period. 

In the t\vo extremes of climatic conditions there 

are what appear to be two distinct biotypes which, 

although lacking really significant qualitative diflerences, look quite different as a result of the combined effect of a number of apparently minor 

quantitative differences. Two localities, each havFIGURE 37.-Tlirinux parviflora: A, Subspecies parvipora 

growing at “R”-ridge above Charlton, Mt. Diablo (the 

late Mr. L. XVynter assisted in the collection of palms while 

I I\ as ill Jamaica); 13, subspecies finbe~rt2n growing near 

Beverly Hills, Long hlountain, Kingston. 
KIJlIBER 19 53 

ing a large number of individuals in a nearly uniform environment and representing as nearly as 

possible (1) the hottest, driest, lowest elevation and 

(2) the coolest, wettest, highest elevation, were selected for intensive study of the widest range of 

variation in the species. Each population was selected primarily for its ecological situation and for 

having an adequate sample of individuals in a 

relatively accessible area. See the section on Morphology for an explanation of the method of 

selection of plants and parts for measurement and 

study. 

It will be demonstrated under the section on the 

typification of Thrinax parzrifZo~a that the characters of Thrinax, at the higher elevations of Mt. 

Diablo, most closely correspond with characters 

drawn from the type specimen and original diagnosis of the species. These plants, typified by a 

large sample taken at collection locality #lo on 

Hollymount Hill at 792.4 ni (2600 ft) elevation, 

represent one extreme in the overall variation of 

the species. Figure 37A illustrates the typical “pinwheel” form of the leaf and the open crown on tall 

slender trunks. In addition the very short, blunt or 

acutely pointed hastula and the relative absence of 

an abaxial hastula, glabrous to glabrate (Figure 

~OC,D,E) inflorescence branches, generally short pedicellate flowers or fruits, and short anthers are characteristic of the plants in this locality. Inflorescences 

are shorter than the petioles, erect except in fruit, 

and the lowermost branches of the lower primary 

branches are occasionally branched more than once. 

Flowering is very irregular but occurs between 

December and March. 

Also characteristic of all plants at the higher 

elevations are certain biotic changes of the inflorescence and fruit (described under Phytomorphosis 

and Zoomorphosis in Thyinax paruiflom). These 

changes have led to considerable confusion and 

misinterpretation. In fact one specific epithet, now 

in synonymy, is descriptive of the change in the 

character of the fruit, and the plants to which it 

applied have been suggested as having some significance in evolutionary theory. In a discussion of 

the durian theory in relation to palms, Corner 

(1966: 180) wrote: “Perhaps in this durian complex, 

there should be added Thrinax tesselatus [sic] of 

Jamaica, the fruits of which appear to have small 

flattened warts as in Pholidocaipus.” 

In contrast with the Hollymount Hill “biotype” 

the plants of the lower elevations, below 365.76 m 

(1200 ft) from the base of Mt. Diablo south to 

Portland Ridge, and typified by collection locality 

#22 at Cockpit, Clarendon, have quite a different 

aspect somewhat resembling the plant in Figure 

37~. The heavy crown, with relatively broad leaves 

.A 

F 

FIGURE 38.-~-c, Frequency distribution of anther lengths; D-F, range of pedicel lengths. A, D 

are Thrinnx pnruifiora from Devils Backbone; B, E are from the Swartz t)pe specimen; and c, F 

are from T. rndintn hlorant Point, Jamaica. (Histograms are based on 100 measurements; bar 

graphs are based on 29 measurements. Measurements in mm.) 
54 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

and slightly drooping segments, supported on a 

short trunk is typical. The adaxial hastula is prominent, long pointed, and often tubular when the leaf 

is fully expanded. The abaxial hastula is also 

conspicuous, frequently forming a triangular projection up to 1.6 cm long. The arching inflorescences equal or exceed the petiole in length, and 

all branching parts including the elongate pedicels 

are densely puberulous (Figure ~OA,B). 

The length of the pedicels, in flower or fruit, and 

the length of the anthers have frequently been 

used as key characters for distinguishing between 

taxa. These characteristics have been given some 

emphasis in this study to test their usefulness and 

to emphasize the danger inherent in the use of 

small samples such as are available on herbarium 

specimens of palms. It can readily be seen in the 

histograms in Figures 19, 38 that pedicel length is 

certainly not a good character. 

Figure 38~,c illustrates the variability of anther 

length in Thrinux parviflora and T. mdiata. If only 

two localities are considered, the character might 

appear useful; however, plants with very short or 

very long anthers occur in the same population. 

This situation occurs in nearly all the characters 

tested. Given only two extreme localities, which 

were the basis of Beccari’s work, because the): represent classical collecting areas, two quite distinct 

taxa are the result. Additional collections however, 

lrom many localities over the entire range of the 

species throughout the island fill in the gaps and 

blend the overlapping measurements, resulting in a 

kind of clinal variation of nearly all characters. 

Accumulation of mutations expressed as certain of 

the extreme variations, with subsequent introgression, might be achieved as a result of the fact that 

the highland biotype flowers from November to 

March, while the lowland plants flowered from 

April through September. 

Throughout the range of T. pa~vif7o~-cr, definite 

trends in leaf form and trunk size exist which appear 

to follow certain gradual changes in climatic conditions. The most significant variations in the physical environment that appear to influence the phenotype are changes of moisture availability in the 

areas of different rainfall and of temperature with 

differences in elevation. Consistent east-west trends 

may also be due to combinations of these factors. 

Several features such as branching and puberulence 

of the inflorescence rachillae and hastula form, 

although different at the two principal environmental zones, seem to vary little throughout the 

range of the species and appear to be characteristic 

of particular ecotypes. 

Caudex: The caudex diameter and height of 

mature individuals are extremely variable even 

within a small local population, but the largest 

mean diameters and shortest trunks occur in the 

hot, dry, exposed areas of St. Andrew, St. Catherine, and Clarendon. Plants with trunks having 

smaller mean diameters are found in regions of 

greater rainfall toward the west and in the cool 

moist gorges (i.e., Cane River, Rio Cobre), or at 

the median elevations of the hills or Cockpit Country. The very tall plants of smallest trunk diameters are found only at the cool, moist, high elevations or in exceptional areas of unusual climatic 

FIGURE 39.-Polymorphic leaves of Thrinnx pnrviporo: G. R. 

Proctor, of the Institute of Jamaica, holds a leaf from a 

juvenile plant in hi5 right hand, and a leaf from a flowering 

sire plant in his left hand; near Ramgoat Cave, in the Cockpit country of Jamaica. 
SUhIBEK 19 55 

conditions such as that described under Donkey 

Trail and “R”-ridge. 

Leaf Polymorphism: Among the plants of Thrinax 

pawifiora growing at the higher elevations, there is 

a striking change in leaf morphology from seedling 

to maturity and eventual exposure of the crown at 

tlie canopy. The seedling stages up to the formation 

of the trunk are typical for the genus. The change 

in leaf form, however, subsequent to the first appearance of a trunk is possibly unique among fanleaved palms (Figure 39). 

The leaves produced at tlie time of trunk formation are circular in outline and rather flat or 

slightly funnel shaped with tlie free part of the 

segments rigid. As the trunk elongates the leaves 

attain their greatest diameter, have a broad palman, and the segments arch slightly. With increased age oE the plant the palman is slightly 

smaller and the longer segments tend to droop. 

When the plant reaches maturity the leaves appear 

to be much smaller as a result of the much reduced 

palman and the fact that the drooping segments 

begin to curl. 

Fdly mature plants in tlie full dense shade below 

the canopy may have leaves with a fairly broad flat 

palman and drooping curled segments such as are 

illustrated in Figure Sin; however, when the plants 

are exposed either on a cliff face or above the canopy they assume a strikingly different form. The 

basal portion of the blade folds up and forward, 

the palman is very small and uneven, and the 

segments are twisted and tightly coiled (Figures 

8, 39). At this latter stage the blade often appears 

as a “pinwheel” on an excessively long slender 

petiole. The petiole in fact is shorter on older 

plants, but the much contorted blade creates an 

illusion of a longer petiole. 

Vm-iabilify of the Leaf Elsewhew: The form of 

the leaf blade throughout the range of tlie species 

is the most highly variable characteristic of the 

entire complex of variation, reflecting in effect different phases of the polymorphism exhibited tluring the development of plants at the highest 

elevations. The change in shape or form is in fact 

simply the result of quantitative changes in the 

component parts of the leaf. The form ol the leaf, 

which must not be confused with outline, is three 

dimensional resulting from varying degrees of folding, twisting, and curling of the palman and segments. The overall trend appears to be a decrease 

in siLe of parts with maturity, aging, increased 

height and exposure and with change from hot and 

dry to wet and cooler climates. 

The change in leaf form during maturation of 

individuals, throughout the greater portion of the 

population, is simply the production of larger 

leaves accompanied by increases in the number, 

width, and length of segments, and the breadth of 

the palman. Mature plants, not yet having reached 

the canopy, produce larger, more heavily textured 

leaves, juvenile types showing a tendency for the 

lower portion of the blade to be folded upward. 

In the hot dry plains of Clarentlon near Palmers 

Cross the mature leaf blade (Figure 7) has a broad 

uneven palman and wide very leathery segments. 

Elsewhere in the dry evergreen thicket formations 

of St. Andrew, St. Catherine, and Clarendon, the 

leaf blade is not quite so leathery, tlie broad palman 

is relatively flatter but with the basal part of the 

blade folded up and forward (Figure 37n), and the 

segments arching or drooping. The leaves of plants 

exposed at the canopy or in a clearing exhibit a 

narrower palman and increasingly lax segments. 

Tall, very old plants have leakes in which the changes 

just described are even more strongly expressed. In 

certain areas of lower temperatures and/or higher 

moisture availability (i.e., Cane River Gorge, Rio 

Cobre Gorge, Fern Gully, and westward from 

Clarentlon) mature plants have leaves with proportionally smaller palman and narrower segments 

which twist or curl slightly (Figure 37A). 

In regions of higher rainfall in tlie west and 

northwest of the island such as at Negril Hill, 

Silver Spring, Lances Ray, Dolphin Head, and 

TYindsor Cave, the species exhibits a markedly reduced leaf with a narrow uneven palman, and 

narrow twisted segments. This form of leaf blade 

is expressed to different degrees depending on maturity or exposure but appears almost intermediate 

between the two extremes discussed earlier. During 

the early part of the study, plants having the latter 

leaf form were classified along with plants of the 

highest elevations until it was realized that the 

dense puberulence on the inflorescence branches 

placed the plants more consistently among those 

of the lower elevations. In Cockpit Country, plants 

of median elevations (hut on exposed drier locations) resemble the lowland forms most closely. 

In regions of still greater moisture availability 

and cooler temperature?, as on the upper levels of 
56 SXIITHSONIAN CONTRIBUTIOSS TO BOTASY 

Dolphin Head, Somerset, Top Hill, Albion Mountain, and Mt. Diablo, the leaf blade of mature 

plants is smaller and more tightly curled and 

twisted in proportion to increased elevation and 

exposure at the canopy. The greatest extreme in 

reduction in size of leaf parts accompanied by a 

great amount of folding, twisting, and curling occurs on the highest levels of Mt. Diablo where the 

plants (Figure 8) exhibiting these characteristics 

are very tall and exposed above the canopy. 

Hastula: Although quite variable throughout the 

range of the species, at the higher elevations the 

hastula is generally short and blunt adaxially and 

lacking or vestigial on the abaxial surface. This is 

one of the few characters of which measurements 

do not appreciably overlap. 

With the exception of the plants at the highest 

elevations, the adaxial hastula is quite prominent, 

long pointed, and frequently tubular. The abaxial 

hastula is also conspicuous whether as a flap of 

tissue projecting from the apex of the petiole or 

as a well-defined triangular extension with a retuse 

apex. In the sample studied at Cockpit in Clarendon, a specimen was collected in which the abaxial 

hastula was developed into two slender processes 

projected up along the undersurface of the blade 

for 20 to 30 cm (Figure 13c,~). Although not noticed at the time the specimens were collected, two 

leaves taken from the same plant exhibited the 

same anomalous condition, suggesting perhaps that 

all leaves produced by the plant possessed similar 

processes. 

Inflorescence: The usually arching inflorescence 

equals or exceeds the petioles among the plants of 

lower elevations but varies considerably in length 

and aspect at the higher elevations where it may 

be erect and much shorter than the petiole. 

Of particular interest is the occurrence of pimary branches which are twice branched, a unique 

condition so far as is known among members of the 

Thrinax alliance. As a rule the individual primary 

branches are once branched. At the lower elevations 

the ultimate branches are commonly forked but 

never as elaborately branched as those at the highest elevations. Several specimens have been collected 

on Aft. Diablo in which the lowermost primary 

branches are twice branched producing a secondary 

condition resembling the primary branch from 

which it originates. These highly branched secondary branches, however, are subtended by the same 

triangular nonsheathing bracteoles as are the simple unbranched ultimate branches. 

Pedicels: One of the key characters used to distinguish between the “species” of the Thrinax 

pU7aifiol-U complex, and among species of other 

genera as well, is the length of the floral and fruit 

pedicels. As was mentioned earlier the importance 

given to the length of the pedicels by the various 

workers in the genus has necessitated particular 

attention to testing its reliability. The results presented in graph form in Figures 17 and 19 illustrate the uselessness of the character in Jamaica 

and emphasize the need for adequate samples irom 

throughout the entire range of the species complex. 

It also points out the danger of basing taxonomic 

conclusions on too few characters and in certain 

cases upon the wholly inadequate presently available herbarium specimens. 

Samples from 144 plants in 32 different localities 

totaling some 12,000 measurements are tabulated 

in Figures li and 19. It can be seen readily that any 

attempt to correlate pedicel length with a particular phenotype or locality is futile. The frequency 

histograms (Figure 19), representing only three 

localities, alone show so much overlap at the higher 

frequencies that one can conclude the shortest 

pedicels (lo occur at Hollymount Hill and the longest occur at Cockpit, but these extreme areas share 

the identical lengths with such great frequency as 

to be of hardly any taxonomic significance. TVhen 

all 32 localities are considered together as in Figure 

li the ranges and means of variation overlap considerably. They show a general tendency to increase 

gradually from high to low elevations. 

Pubel ulence: The entire population of Thi innx 

pawiflora is divided into two fairly distinct expressions of puberulence on inflorescence branches. 

This character, never having been mentioned in 

any study of the genus, provides the only fairly 

consistent means, apart from the hastula, for separating the species into two biotypes. Throughout 

the range of distribution of the species, with the 

exceptions to be mentioned below, all parts of the 

inflorescence branches are densely puberulous. This, 

as far as can be ascertained, is another unique character in the Thrinux alliance; certainly no other 

members of the genus have been reported to have 

puberulent rachillae. Although the presence of 

puberulence can sometimes be determined by the 

naked eye, it is usually necessary to use a lens of 
SUMBER 19 57 

at least X 8. The degree of puberulence does not 

vary much at the lower elevations (Figure ~OA,B). 

On the upper peaks and ridges where cool mists 

and clouds prevail (e.g., Hollymount Hill, Union 

Hill, Grier Mount, Devils Backbone, Dolphin 

Head, Somerset, Stirling Castle, Ramgoat Cave, 

etc.), there is a striking change in the puberulence. 

The plants here produce inflorescences with apparently glabrous (Figure 40~) or glabrate (Figure 

40~) branches. Frequently the puberulence is limited to widely scattered hairs in lines or patches 

usually on the rachis or peduncle. It is doubtful 

that any plants produce inflorescences which have 

truly glabrous branches, but it is difficult to see the 

hairs at anthesis and pollen grains can easily be 

mistaken for puberulence. Occasionally infloresFIGURE IO.-Different degrees of puberulence exhibited by inflorescences of Thrinax parvifiora, 

ultimate branches: A, Cockpit, Clarendon; 13, Spring Garden, St. Catherine; c, Devils Backbone; 

D, E, Hollymount Hill. 
58 

0 

LOCALITY # 

4 

5.0 

52 

5k 

. 

22 

41 

.. ,.A. i 

.. 

* = low 

41 

SMITHSONIAN CONTRIBUTIONS TO BOTANY 

15 14 13 12109 8 7 5 

... 

... 

... 

... 

... 

... 

... .*. 

. . . 

. 

. 

. 

. 

b 

. 1. . ... . .' .. .. 

.. 

.. 

.. 

.. 

'I 

I 

\ 

'%I.-()-, - 

457 't 

$. ..... 304 - 

914 - 

762 - 

*. . *. .-it; 152 - \ir...-. Ir ........... * .. 

.and phenotype 0 = high elevation phenotype 

May 1- . Pen w p - 1 *.eIn ' I 98 \ a 

W 

3 :402,000 

Suanish Town 

*- 

A* ST. ANN 

'. 

FIGURE 41.-Transect across central Jamaica, showing pedicel length and phenotype, from 

lowest to highest elevations where Thrinnx parviporn occurs. The large dot in the bar graphs 

represents the mean length of the pedicels, the solid line represents 90% of all measurements, 

and the broken line indicates 5% of the total taken off each end of the range, 
SUXIBER 19 

cences of plants in exposed localities produce 

branches with considerable puberulence (Figure 

40c). Insect grazing on the branches of plants at 

the higher elevations often entirely denudes the 

epidermis preventing accurate determination. 

In certain localities such as at Dolphin Head and 

Windsor Cave phenotypically similar plants growing in the same general area may produce inflorescences with dense puberulence or almost glabrous 

branches. Transplant experiments would be most 

helpful to test the effect of climate on the degree of 

puberulence. 

Transplant Expel iment: An attempt was made 

to transplant mature individuals from the highest 

elevations into a garden at the University of the 

West Indies Botany Department to be grown with 

individuals removed from low elevations. The elevation at Rlona is approximately 600 feet, and the 

area frequently suffers from prolonged dry periods. 

The primary purpose was to obtain flowering material for cytological studies dependent on the production of inflorescences within the year or two 

following transplanting. Only one plant produced 

inflorescences and this was very soon after having 

been transplanted. The flowers produced nonviable 

pollen. 

Another possible and valuable result of the experiment would have been the observation of the 

degree of puberulousness on the inflorescence 

branches of plants removed from the high elevations. It was strongly suspected that there would be 

an increase in puberulousness if the high-elevation 

plants formed inflorescences in the hot dry climate 

of Mona. Leaf form and pedicel lengths produced 

at Mona would also have provided valuable information about possible genetical differences between 

the two apparent biotypes. This experiment has 

been terminated as a result of an abnormally long 

drought and a severe water shortage from January 

to September of 1967. Most of the plants remained 

green and in fact produced new leaves during the 

growing season of 1966; however, lvatering was 

stopped in the spring of 1967, and during two 

weeks of particularly hot drying winds, without 

rain or water, nearly all leaves rapidly turned 

brown and the trunks began to Tvrinkle from slirinkage. All plants have since died due to the continued 

drought and lack of water. 

Seeds from many remote areas have been germinated and the resulting plants ivill be transplanted in a test garden. The comparative results 

of seedling transplants will take many years because of the extremely slow growth rate characteristic of palms in this genus. Seedling palms grown 

in containers will become established more easily 

if root damage is minimized and water is available. 

It is the earnest desire of the author to bring together in one test garden seedlings of all taxa in the 

genus for comparative studies at some future date. 

TRANSECT FROM PORTLAND RIDGE TO HOLLYMOUNT, 

JAMAICA.-A line drawn from Portland Ridge, in 

the south, to the northern slopes of Mt. Diablo 

(Figure 41) passes through regions of low to high 

elevations from sea level to about 914 m (3000 ft), 

and from hot, dry nearly xerophytic conditions to 

cool, moist mesophytic woodlands and high pinnacles frequently bathed with mist. The rainfall 

varies from less than 126 cm (50 inches) per year at 

Portland Ridge to more than I78 cm (70 inches) 

per year on the heights of Rlt. Diablo. Along the 

line, changes in temperature and moisture availability are mostly gradual up to the middle elevations on Mt. Diablo where, as a result of the 

combined effect of exposure, elevation, and the 

very steep escarpment, the changes are more abrupt. 

At the elevation where cloud formation most frequently occurs, noticeable differences in the climate 

and flora are evident over a very short distance. 

Thrinax parvipora grows on practically every natural outcrop of limestone along the transect line. 

During the present study numerous collections 

were made in nearly every accessible area along an 

irregular line froin south to north, and on Rlt. 

Diablo, in an attempt to obtain adequate material 

over a range of variable ecology. The collections 

were also part of an investigation to determine the 

distinctions for maintaining two taxa in the region, 

one in the lower elevations (T. parvifiola) and one 

at the highest elevations (T. tessellata). The principal means of distinguishing between these two 

species had been the supposed absence of pedicels 

and the appearance of the fruit in the latter. The 

tessellated appearance of the fruit at the higher 

elevations, resulting from fungal infection described 

earlier, and the length of the fruit pedicels are 

poor characters which were based on Tvholly inadequate material. 

The transect runs through two of the three intensive study areas. Samples of inflorescences were 

taken from every available plant at both Cockpit 
60 SMITHSONIAK CONTRIBUTIONS TO BOTANY 

and Hollymount Hill. In addition pedicel measurements were taken from every collection locality 

along the route of the transect. These measurements are all compared in Figure 41, and it is obvious (as has already been shown) from the results 

that the length of the pedicels cannot be used for 

separating taxa. Although the high-elevation plants 

have a predominance of short pedicels, those of 

lower elevations exhibit an abundance of pedicels 

in the same length ranges, and there is considerable 

overlap at the 90 percent level. 

Only two apparently reliable characters can be 

used to characterize the high- and low-elevation 

phenotypes along the transect: the hastula and the 

degree of puberulence on the primary branches of 

the inflorescence. The designation in Figure 41 for 

lowland phenotype represents plants with long, 

pointed hastulas and densely puberulous primary 

branches, accompanied usually by large leaves and 

relatively short and stout caudices. The designation for high-elevation phenotype represents plants 

with short, acute or blunt hastulas and glabrate 

(Figure 40~) to lightly puberulent (Figure ~OC,D) 

primary branches. 

Additional measurements are included in Figure 

18 comparing variability at the three intensive 

study areas. Bar graphs giving the range of variation and means for the various organs of plants 

along the transect route may be found in Read 

(1968). 

Blue Mountain Trail: Along the southern face 

of Mt. Diablo an exceedingly steep escarpment 

rises nearly 609 m (2000 ft) above the valley. Along 

most of the escarpment, which faces south, climatic 

conditions up to about 502.92 m (1650 ft) elevation 

are very similar to those at lower elevations. Full 

exposure to the sun, particularly in the winter 

months, perfect drainage, and average rainfall permit a dry evergreen, thicket-type vegetation in 

which the palms are almost indistinguishable from 

plants growing near sea level on Portland Ridge. 

At approximately 609 m elevation the vegetation 

changes to open woodland in protected valleys and 

gorges, and tall, slender plants of the typical highelevation palm dominate the exposed ridges and 

rocky pinnacles. There does not appear to be a 

transition zone for the palms along the trail, because suitable rocky outcrop was not encountered 

between 502.92 and 762 m elevation. It is important 

to note that the point between 518.16 and 609 m 

(1700 and 2000 ft) elevation is the altitude at which 

clouds generally form and obscure the peaks and 

ridges, commonly throughout the year, but more 

frequently in the late summer and winter months. 

The clouds and mists common above 609 m elevation on Mt. Diablo result partly from and contribute to the higher moisture availability and 

cooler temperatures reflected in a different flora. 

The greatest extremes in phenotypic expression 

are coincidentally found growing on the southfacing escarpment of Mt. Diablo above an area 

known as Charlton. At locality #13, between 457.20 

and 502.92 m (1500 and 1650 ft) elevation, several 

palms exhibit among themselves the largest trunk 

and leaf dimensions, and although two of the 

plants in the group had pedicel lengths averaging 

within the normal range of means for lowland 

lorms, the third plant exhibited exceptionally long 

pedicels which caused the mean for the group to be 

among the longest pedicel lengths (Figures 17, 41) 

of any population on the island. 

Near the upper limit of the escarpment, overlooking the group of exceptional plants just mentioned, typical high-elevation plants occur between 

609 and 807.72 m (2000 and 2650 ft), in the cloud 

zone. The very tall, slender-stemmed palms with 

very small tightly folded and curled leaf blades 

grow among somewhat dwarfed thicket wherein 

occur numerous epiphytes, ferns, and herbaceous 

plants. 

“R”-)idge: ’4 short distance to the west of the 

Blue Mountain trail, a spur extends southward 

from Mt. Diablo and descends to 457.2 m (1500 ft) 

elevation at a pass over which the Ewarton-’IVorthy 

Park road crosses. Apparently the spur and ridge 

provide a barrier to moisture-laden prevailing 

winds from the east, for the appearance of the 

vegetation seems to indicate a rapid increase in 

moisture availability as one ascends a short distance 

along the road to the pass. At approximately 365.76 

m (1200 ft) the road passes from an area of exceedingly dry, nearly xerophytic rocky outcrop to an 

area of mesophytic woodland on an east-facing 

slope. Thiinnx parvif?ora exhibiting the lowland 

phenotype are common on the slope. X short distance uphill, but beyond a bend in the road, the 

vegetation changes to dense woodland where tall, 

slender palms of the high-elevation phenotype are 

found. Patches of mesoph) tic woodland alternate 

with xerophytic scrub between 396.24 and 457.20 m 
NUMBER 19 61 

(1300 and 1500 ft) elevation along the road, and it 

is possible to observe both phenotypic expressions 

of T. parviflora growing a short distance apart but 

still apparently in different habitats. Near the pass 

at 457.2 m (1500 ft) the vegetation mostly resembles moist woodland, which is usually limited to 

much higher elevations on Mt. Diablo. The whole 

of the ridge area is one of strong ecological contrasts. 

On a small limestone and marl ridge, at the 

highest elevation along the road, there is a strange 

mixture of both high mountain and lowland species 

of plants other than palms (e.g., Sloanea jamaicensis 

and Bursera simaruba) growing side by side. Here 

too was found the unique situation where both 

phenotypes of T. parviflora are growing very near 

one another. Retaining their peculiar individuality, 

the two phenotypes are distinguished by the tightly 

congested leaf blade with twisted segments and 

more slender trunk of the high-elevation form (Figure 42~,c) as compared with the larger, flat or 

simply folded leaf blade with straight or drooping 

segments and much heavier trunk of tlie lowland 

form (Figure 42~). In attempting to verify these 

apparent differences it was found that the old inflorescences, taken from plants exhibiting the characteristics of the high-elevation phenotype, were so 

completely damaged by insect grazing that they 

were useless for comparison with the densely puberulous inflorescences taken (collected in young fruit 

in July) from plants exhibiting characteristics of 

the lowland phenotype. The occurrence of two 

different phenotypes (differing it must be stressed 

only in quantitative characters which overlap considerably with plants elsewhere on tlie island) in 

the same population, while proving nothing and 

raising numerous unanswerable questions, certainly 

suggests the existence of two genotypes, at least in 

that particular locality. 

Among a group of tall, slender plants growing 

on a steep slope in a depression behind the ridge, 

where even the lowland form attains considerable 

height (up to 9 or 10 m), two plants were observed 

which might represent intermediates between what 

may now be considered two genetic biotypes. Both 

FIGURE 42.-Phenotypes of Thrinax paruiflora found growing within a short distance of one 

another on “R”-ridge, at about 457 m ele\ation, along the Ewarton-\\’orthy Park road. The 

two plants at the left are tjpical of the two extreme forms; the plant on the far right could 

possibly be a hybrid between the two biotypes. 
62 S.MITHSONIAN CONTRIBUTIONS TO BOTANY 

FIGLRE 43.-Region of the Cockpit country showing extent of deep continuous box canyon running from Barbecue Bottom to Burnt Hill. Adapted from the topographic maps of the 

Directorate of Colonial Surveys, D.C.S. 1st edition 1954. Jamaica l/50,000. Further explanation 

will be found in the text. 
SUXIBER 19 63 

of the intermediates exhibited flatter leaf blades, 

intermediate in size, with rigid segments (Figure 

41~), and the trunks were intermediate between 

plants exhibiting the clearly recognizable phenotypes of high or low elevations. It should be mentioned that apart from the area just described it is 

almost impossible to be certain about the position 

of certain plants growing in exposed situations at 

middle altitudes without resort to examination of 

the puberulence on the inflorescence branches. In 

the population described above both forms appear 

most robust and the differences between them appear somewhat exaggerated. 

The area here in question was not found until 

very late in the study and, although of great significance, it is regretted that time and circumstances 

did not permit additional field xvork. It remains an 

exceedingly interesting area for future concentrated 

study when plants of both forms can be compared 

by study of inflorescences at anthesis and in fruit. 

DONKEY TRAIL TRAKSECT.-In the northeastern 

corner of the “Cockpit Country” in Jamaica, a 

series of large interconnected cockpits extends four 

miles southward along the road from Kinlosr to 

within half a mile of Burnt Hill intersection. The 

cockpits (indicated by solid shading in Figure 43), 

including the one at Barbecue Bottom, vary from 

nearly a mile wide in the vicinity of Campbells, to 

only 100 or 200 m wide at the southern end. The 

formation resembles a “box canyon” with walls 

100 to 200 m high throughout its length and opens 

to the north where it is exposed to the prevailing 

northeasteily winds. Figure 43 illustrates the major 

topographic features of the region. 

In mountainous regions, increase in elevation is 

normally accompanied by a gradual decrease in 

temperature, and cloud formation is usually restricted to the higher peaks and ridges. An anomalous situation occurs in these cockpits where the 

usual climatic conditions are inverted. High ridges 

surrounding the southernmost cockpit (Figure 44), 

although rising above 548.64 m (1800 ft), support 

an open, dry evergreen thicket which resembles 

that on the lower slopes of hlt. Diablo. Likeivise, 

plants of Thyinax pawipoin growing on the ridge 

very closely resemble those of much loTver elevations elsewhere. As one descends into the cockpit 

the air temperature decreases noticeably in a very 

short distance and the vegetation changes from dry 

evergreen woodland on the upper slopes to wet 

forest on the lower slopes and in the bottom 

Thrinax pawipora growing inside the cockpit (Figure 44n) exhibits the phenotype usually associated 

with the highest and wettest elevations of Mt. 

Diablo. 

Because extremely different phenotypes were 

found growing a short distance from one another, 

a transect study was made in order to compile 

additional information in support of ecoclinal variation in Thrinax parviflora. During a 48-hour 

period from 25 to 27 May 1967, a climatological 

and morphological study was made along a transect 

projected through a population of T. paruiflora on 

the south side of the cockpit at “R” in Figure 44. 

FIGURIC 44.-Donkey Trail special area, enlatged from section 

indicated in Figurc 43: A, start of the donkey trail; B, C, 

points at which climatological readings were made, Further 

explanation in the text. 
64 ShIITHSONIAX CONTRIBUTIONS TO BOTANY 

elevation in feet 

1825 

LOW Elevation 

1 1740 

Phenotype 

May 

tF 

RH 

tF 

RtI 

High Elevation 

Phenotype \ 

1707 

1700 

1695 

1690 

1685 

RH "? 1500 

1400 tF 

RH 

25th 

P.M. 

om 

03 

IA o> .. .. 

83 7; 

78 7C 

87 9E 

76 70 

89 95 

76 

89 

75 

96 

26th 

, . . . . . . . N cu mc- 4 

81 79 77 76 

72 82 

80 74 

76 89 

75 74 

91 91 

27th 

A.M. 

In0 3m 

Lnc- 

.. .. 

71 73 

69 72 

88 86 

59 

38 

FIGURE 45.-Donkey Trail Cockpit profile (tF = temperature in degrees F; RH = the ielatiie 

humidity; o = matuie plants; u = juienile plants; Xertical scale, 1 cm = 10 ft; angle of slope 

55-60 degrees). 
SUXIBER 19 

I,ocnlity 

65 

T?mfieratzires 

iiiayi- minimum muin 

Flowering 

season 

The transect originated on the highest ridge at 

556.26 m (1825 ft) elevation ("E" in Figure 44) 

and extended down into the cockpit for 47.24 ni 

(200 ft) to 509.02 m (1670 ftj elevation along a 

belt 3.05 m on each side of a string stretched between the two points. The upper 15 'm of the 

transect consisted of nearly vertical exposed cliffs 

above the donkey trail. Below the pass a scree slope 

at an angle of 55" comprised the remaining 32 m. 

The donkey trail originates at point "A" in Figure 

44, passes over the ridge at 539.49 m (1770 ft), and 

continues diagonally across the path of the transect 

providing access to tlie stations where climatological 

information was gathered (Figure ~~B,c,D,E). 

A constant recording thermometer i~as pIacet1 at 

the highest (most inaccessible) point at 556.26 m 

(1825 ft) elevation, near the base of a large palm. 

A rnaxiinum-minimum recording thermometer was 

placed at the 509.02 m (1670 ftj level. Periodic 

recordings of temperature and relative humidity 

were made using a sling psychrometer and the percentage relatiye humidity was computed with the 

aid of the Psychorometric Tables compiled by C. F. 

1Iarvin.l' The information obtained is recorded in 

Figure 45 and is compared with the distribution of 

phenotypes on the side of the cockpit. 

Mango Tree Hill, one of the original areas of 

intensive study, is about a mile to the southwest of 

the Donkey Trail study area. The palms mostly 

exhibit the lowland phenotype antl closely resembIe those on the uppermost ridge at the Donkey 

Trail area. A maximum-minimum recorded thermometer was also maintained on Mango Tree Hill 

throughout the 48-hour period for comparison rvi th 

temperatures recorded on the Donkey Trail ridge 

(Table 2). 

Although the sample studied at the Donkey Trail 

site is small and the period covered by the climatological data is short, certain significant trends antl 

features are thought to be worth noting. A marked 

difference in climate between the ridge and slope 

of the cockpit is not only evident in the differences 

in temperature and percentage of relative humidity, 

but is also reflected in the distribution of species 

of certain plants. Hohenbeyio xmota, H. polycephalo, and Tillnndsin sp. aff. fnsciciilatn are plentiful on the ridge but entirely absent on the slope 

'I I'uhlished by the C.S. TVeather Bureau, TVnFhington, D.C. 

(1V.n. No. 235, U.S. Department of Commerce, 1041). 

Vango Tree Hill 

Tiansect 1825' 

rianrect 1670' 

below. Gzizrnclnia lingulata, ferns, and herbaceous 

plants occur on the slopes but are entirely absent 

on the ridge. IYere it not for the fact that the sky 

was overcast during part of the study, the disparity 

in the temperature and relative humidity readings 

between the ridge and the slope might have been 

even greater. At all times a strong cool breeze blew 

through the Donkey Trail pass at 539.49 m (1770 

ft) elevation where the temperature was as much 

as 1.68"C lower on the northern side, a distance of 

only twenty feet. Dew and fog began to form in the 

bottom of tlie cockpit soon after 7:OO p.v. The fog 

persisted up to the 487.68 m (1600 ftj level until 

after 8:00 A.M., when the sun's ra)s reached tlie 

lower levels of the cockpit. During the Ivinter 

months when the angle of the siin would be to the 

south, longer periods of shade and fog, along with 

a greater difference in temperature between the 

ridge and the north-facing slope of the cockpit 

would be expected. The conditions just described 

for the inside of the cockpit resemble conditions 

pielailing above 609 m (2000 rt) elevation on the 

>It. Diablo range of mountains. 

It can be seen from a study of Table 9 that in 

each organ studied size differences occur, but they 

are not great enough to be considered important; 

however, the more congested and twisted leaf hlatles 

and taller, more slender cautlices of the plants in 

the cockpit create a distinct impression of two 

distinct biotypes. In Table 3 each elevation recorded represents a single plant along the transect. 

Each mearurement, ivith the exception of caudex 

height antl diameter, represents the average of four 

measurements for each plant. ,411 characters <tudietl, 

with the exception of the caudex height, tend to 

decrease gradually in size with decrease in elel ation 

within the cockpit and could probably be correlated 

with the lower temperature and increased humidity. 

Although numeroils seedling., of TIii inq1c pn).uifloro 

84" F 66" F Vay through August 

83" F 50" F \Ia\ through 4ugust 

5Cjo I' Gi" F Januai\ thiough March 
66 

Selected characters 

SMITHSONIAN COKTRIBUTIONS TO BOTANY 

1825 1815 1810 1750 1740 1707 1700 1695 1690 1686 

Petiole length in cm ................. 

Petiole width at the 

sheath in cm ............... 

Petiole width at the 

apexincm ....................... 

Hastula (adaxial) 

length in cm ................. 

Hastula (abaxial) 

lengthincni .......... 

Leaf segment number ......... 

Leaf segment length 

in cm ........................ 

Segment width at the 

widest point in cm ............. 

Palman length in cm ....... 

Caudex diameter in cm ... 

Pedicels of fruit, 

Degree of puherulence 

Caudex height in m ... 

mean length in mm ...... 

relates to Figure 40 . . 

72 79 143 68 68 75 67 78 72 85 

2.1 1.8 2.5 1.3 1.1 1.5 1.2 1.6 1.6 1.7 

1.8 1.5 2.0 1.0 1.0 1.1 1.1 1.2 1.2 1.4 

2.5 3.4 2.1 0.9 1.3 1.0 0.6 - 0.9 0.8 

0.5 0.4 0.3 0.1 0.1 0.1 0.1 0.1 0.1 0.1 

54 43 55 41 38 45 44 42 41 44 

74.0 62.0 85.0 50.5 51.5 53.0 46.5 50.0 54.0 63.0 

4.2 5.3 6.6 3.5 3.2 4.6 4.3 3.8 4.3 3.8 

11.2 21.2 32.5 14.5 14.5 14.7 19.5 9.5 14.5 21.2 

10.0 8.0 11.0 7.7 6.0 6.5 6.2 6.2 6.1 5.5 

5.0 1.4 1.0 3.3 3.6 4.0 4.0 4.0 5.0 5.0 

1.3 1.7 - 1.0 0.6 1.0 0.6 1.1 1.1 0.6 

BB- -C-D-EE 

occur below 502.92 m (1650 ft) elevation, inside 

the cockpit mature plants are absent, and below 

487.68 m (1600 ft) even seedlings were exceedingly 

rare. 

Thrinax Swartz 

Thrinnx Sw., Prodr. pp. 4, 57. 1788.-Linn., Gen. PI. ed. 8 

(Schreb. ed.) 2:772. li9l.-Slv., FI. Ind. Occ. 1:613, t. 13. 

1797.-Linn., Gen. PI. ed. 9 (Spreng. ed.) 1:255. 1830.- 

Mart., Hist. Nat. Palm. 3:254, pro partc. 1838.-Drndc in 

Engler & Plant], Sat. Pflanzenf. 2 (3):34. 1887.-I%aillon, 

Hist. PI. 13:317. 1894.--Sarg., Silva 10:49-50, pro partc. 

1896; Bot. Gar. 27:83-84. 1899; Silva 14:79-80. 19OP.-Cook, 

Bull. Torr. Bot. Club 28:534-535. 1901 .-Becc., TTehhia 

2:9-10, 247-250. 1907.-Britt., Torreva 8:240-241. 1908,- 

Becc., Annal. Roy. Bot. Gard., Calcutta (hfartelli ed.) 13: 

327-336. 1933 [“1931”].-Dalgren, Index Amer. Palms 272- 

278. 1936.-Bailey, Gent. Herb. 4: 129-149. 1938; 8:94-99. 

1949. 

Simpsonin 0. F. Cook, Science, n. s. 85:332-333. 1937 [name 

invalid (sine descr. 4at.); type-species: Thrinax microcarpa 

Sargent]. 

Section Porothritiax Drude ex Sargent, Silva 10:49. 1896 

[type-species: Thrinax microcarpa Sargent]. 

TypE-SpEcIEs.-Thrinax pawiflorn Swartz. 

Small to medium, solitary, erect, palmate-leaved, 

unarmed, hermaphroditic, coryphoid palms; caudex 

columnar, tan to gray, smooth or fibrous, obscurel) 

ringed with leaf scars, base usually a mass of roots 

forming a mound on rock substrate. 

Leaves palmate; the sheath fibrous, unarmed, at 

first tubular, velutinous, the petiole with a predetermined abaxial groove below the insertion of the 

sheath which splits on expansion of the bud permitting egress of the inflorescence (at least in 

Jamaican taxa), the petiole above the sheath mostl) 

flat atlaxiallj, conspicuous, various in outline, abaxially a ridge, flap, or small projection; blade flabellate, entirely lacking a central costa, adaxial surface 

glabrous, abaxial surface variously lepidote; segments narrowly rhomboid, trullate, or obtrullate, 

fused variously toward the base forming a plicate 

palman, mostly bifid at the apex. 

Inflorescences interfoliar, elongate, erect to arching, divided into numerous, pendulous, primar) 

branches, these mostly simply branched; lowermost 

primary bract bicarinate, inserted about 1 cni above 

the base of the peduncle, others tubular with an 

oblique aperture, all primary bracts densely allpressed lepidote, each enclosing the base of the 

next higher bract and the peduncle of a primary 
SUhIBER 19 67 

branch with its bract, the latter bicarinate and 

bifid, and partially enclosing the flowers prior to 

anthesis, inserted midway along the flattened peduncle of the primary branch; each ultimate branch 

subtended by a narrow triangular bract. 

Flowers bisexual, mostly protandrous, solitary 

on prominent or very short bracteolate pedicels; 

perianth a single series, forming a 6-lobed or dentate cupule, not enclosing reproductive parts; stamens (5-)6-12 (-15); filaments usually straight, 

slender, mostly free; anthers auriculate basally, 

retuse apically, basifixed, locules linear to oblong, 

dehiscent introrsely by lateral slits; pistil unilocular, uniovulate, with a narrow very short style 

flaring upward to a laterally compressed infundibuliform stigma; ovule with a well-developed funicular aril, erect at the base of the locule. 

Fruit small, depressed-globose to globose, white 

at maturity, often with persistent apical stigmatic 

remains and persistent basal perianth; epidermis 

smooth at maturity when fresh; mesocarp thin, 

mealy; seed depressed-globose, smooth, tan when 

fresh, depressed basally at the hilum; endosperm 

homogeneous but intruded partially or completely 

through the center from base to apex by the testa; 

embryo lateral to subapical. 

DISCUSSIOK OF THE GENUS Thrinax.-The name 

Thrinax, derived from the Greek word for “trident,’’ was conceived by Linnaeus the younger in a 

manuscript before his death in 1783. Olof Swartz 

(1788) published the name, accompanied by a 10- 

word diagnosis, omitting any reference to Linnaeus. 

Considering the brevity of Swartz’s original description it is noteworthy that the description in the 

eighth edition of Linnaeus’ Genera Plantmum published in 1791 comprises a quarter of a page. TVhen 

Swartz published his Flora in 1797, he ackno.ivledget1 

that Linnaeus filiits had provided the generic name. 

It is evident from a comparison of the Swartz description of 1797 with the Linnaean manuscript that 

much of the former’s information is in fact based 

on his own observations in Jamaica. In the ninth 

edition of Linnaeus’ Genera Plantarum, editor 

Sprengel cited, “L. fil. (1781)” as authority for the 

genus. The reason for citing “1781” is not clear 

except as it may refer to the unpublished manuscript.12 Swartz clearly indicated that the flowers 

The Linnaeus filius unpublished manuscript was cited 

by TV. H. Aiton in the Preface (p vi) of Ho~tns Kewensis 

in 1789. 

were pedicellate, but Sprengel wrote that they were 

sessile. 

For 42 years the genus comprised but a single 

named species. In 1830, three additional species 

were published by J. A. & J. H. Schultes: T. argentea, T. pumilio, and T. radiata. Of these three 

species only one remains in the genus, for T. argenlea has been transferred to the genus Coccothrinax 

and T. pumilio became the type for a new genus, 

Porothrinnx, a name which cannot be applied (see 

Appendix 11). Eight years later hlartius described 

two more species, T. multiflora and T. barbadensis, 

both of which were later referred to Coccothrinax. 

If the numerous nomina nuda are included, about 

23 binomials had been published in the genus by 

1866. The first attempt to remove discordant elements from the genus was made in 1866 when 

Grisebach listed: “5. Porothrinax piimilio TVendl. 

ined. (Thrinax Lodd.); Wr. 3219e:” without a 

generic diagnosis but by implication based on the 

description of T. pumilio Lodd. ex. J. A. & J. H. 

Schultes. Since T. pumilio cannot with any certainty be applied to any known taxon, it is considered a nomen incertum. Porotlii inax, based upon 

this taxon, was not validly published because it 

lacked a separate generic diagnosis at the time of 

publication. 

In 1887, Otto Drude created three subgenera: Ezithrinax, Hemithrinax, and Porothi inax. Eu-thrinax 

was characterized as having long-pedicellate flowers 

with introrsely dehiscing anthers and a vertically 

sulcate ruminate albumen in the seed, and comprising T. radiata, T. parvipora, and T. multifEora. 

Subgenus Hemithrinax was characterized by a single species, H. compncta, which has nearly sessile 

or short-pedicelled flowers, sessile anthers with extrorse dehiscence and seeds with the uniform albumen penetrated by a broad deep basal cavity. 

Porothrinax was typified by P. pztmilio of uncertain 

identity. 

Although Drude’s treatment was accepted in the 

Silva in 1896, Sargent soon recognized that certain 

discordant elements could be removed by utilizing 

the character of the seed. Thus in 1899:82 he divided the genus into Coccothrinax, with seeds “vertically sulcate by the infolding of the testa into the 

ruminate albumen,” and Thi innx, the seeds of 

which have a uniform albumen more or less deeply 

penetrated by a broad basal cavity. At that time no 

other sati5tactoi-y characters were known for dis- 
68 SMITHSOXIAN CONTRIBUTIONS TO BOTANY 

tinguishing the two genera when seed was unavailable. For currently reliable characters, see Table 4. 

Bailey (1939) did not believe the color of the ripe 

fruit to be reliable, but, except for one unconfirmed report of a white-fruited species of Coccothrinax and the fact that the fruits of Thrinax 

“harrisinna” were erroneously reported to be purplish, the character holds quite well. Le6n (1956) 

wrote that it is possible 

to distinguish without hesitation a species of Thrinax from 

one of Coccothrinax: in the latter case, the sheath is clearly 

cylindrical, commonly formed of more or less rigid fibers 

which are strongly interwoven and in every case persistent 

on the trunk for many years. ... In Thrinax, the sheath is 

more irregular and not long persistent on the trunk. 

Unfortunately Le6n missed the true character of 

the Thrinax sheath that provides the most useful 

field character: the petiole of Thrinax, as indicated 

in Figure 9c, is split in the sheath, which is not so 

in Coccothrinax. 

At the same time he described Coccothrinax, 

Sargent further divided the remaining elements of 

Thrinax into two sections: the Pedicellatne, including the type for the genus and recognized by having 

long pedicels, and the Sessiliporae, containing species 

with the flowers having the appearance of being 

Key to the Species of Thrinax 

1. Inflorescence branches exhibiting numerous conspicuous pedicel remains, exceeding 1 mm 

in length following fruit set (except occasional specimens of subspecies parvipora of 7. 

pnrvipora); adaxial hastula glabrous or with closely appressed inconspicuous scales on 

emergence from the bud region; abaxial leaf surface lacking rows of minute, waxy dots 

associated with sunken stomata. 

2. Leaves of mature plants densely covered abaxially with white or silvery, overlapping and 

interlocking, hyaline, fimbriate scales (leaves of young plants have similar scales but 

may appear green beneath because the scales are less densely disposed); petioles of adult 

plants tan velutinous, abaxially; inflorrscence branches and flowers pink to purple at 

anthesis, primary bracts densely covered with rufous appressed scales; (leaf sheath long 

linguiform, densely, tan, velutinous, Figure 10~) grows naturally only in the interior 

2. Leaves of mature plants concolorous or very slightly lighter green beneath, scales when 

present widely spaced, not touching; petioles of adult plants very soon glabrescent 

abaxially; inflorescence branches and flowers white, ivory, or yellowish at anthesis, scales 

on primary bracts not rufous colored. 

3. Leaves of mature plants concolorous, glabrescent; scales when present minute (difficult 

to see with the aid of an 8 power lens); segments broadest well beyond the palman; 

sheath long lingniform (Figure log), (observed best in the region of newly emerging 

leaves (Figt:re 1 In); inflorescence branches and flowers ivory to yellowish at anthesis, 

the axes densely granulose-puberulose (except subspecies parviporn in which the 

inflorescence branches are usually glabrous-glabrate but then the pedicels toward the 

apex of the branches are very short); grows naturally only southwest and west of the 

3. Leaves of mature plants lighter green beneath, with scattered but conspicuous fimbriate 

scales which have a conspicuous translucent central region; segments broadest at the 

point of fusion; sheath not lingniform, rather deeply V-form (Figures lOC, 11.4): 

inflorescence and flowers white at anthesis, the axes glabrous; common, but grow’s 

naturally only in close proximity to the sea, below 250 ft elevation on islands throughout the northern Caribbean and the Bahamas, and islands off the coasts of Florida, 

Mexico, and British Honduras .............................................. 2. T. radiata 

1. Inflorescence branches exhibiting only small inconspicuous, nartlike, or disklike, pedicel 

remains, less than 1 mm (averaging about 0.4 mm) in length, following fruit set; adaxial 

hastula densely velutinons with white, silky, scales on emergence from the bud region; 

abaxial leaf surface usually exhibiting rows of numerous, minute, white, waxy, dots 

associated with sunken stomata. (Inflorescence arching, exceeding the leaves, branches 

white to yellowish with age; leaves often blue green to whitish abaxially and often exhibiting closely arranged, pale, hyaline, fimbriate scales abixially.) 4. T. morrisit 

of eastern Jamaica ..................................................................... 3. T. excelsa 

Blue Mountains in Jamaica .......................................... 1. T. paruiflora 

....... 
SUhIBER 19 69 

sessile, Shortly thereafter Beccari (1 907) published 

his comprehensive study of American Coiypheae in 

which he also divided the genus Thrinax into two 

sections adopting the groupings described by Sargent but under different names. Beccari’s division, 

however, was based on the degree of intrusion of 

the testa into the endosperm: Euthrinax, having 

the seed completely perforated, and Typhlothrinax, 

having the testa intruding only part way into the 

endosperm. Since Sargent’s interest was only with 

palms of North America it remained for Beccari to 

raise Hemithrinax to full generic status again, 

which, with Coccothrinax and Thrinax, comprised 

the three genera of the subtribe Thrinaceae. In a 

supplement, in English, Beccari (1933) dealt with 

Thrinax in much the same manner as earlier but 

the addition of floral dissections made it a valuable 

adjunct to his earlier work. 

In 1937, Cook of the Bureau of Plant Industry, 

United States Department of Agriculture, proposed 

a new genus, Simpsonia, which was based on Sargent’s Thrinax microcarpa, but since the proposal 

does not conform to Article 36 of the International 

Code of Botanical Nomenclature it is not validly 

published. Bailey (1938: 131) revived the use of 

Sargent’s Pedicellatae and Sessiliporae because “the 

species may vary within themselves in the extent 

of the centralium in the seed.” 

Common Names: As might be expected the common names applied to the members of the genus, 

as well as to the genus as a whole, are almost as 

difficult to straighten out as are the scientific 

names. The first common name to appear in the 

literature was that applied by Sloane (1696). He 

called the palms “thatch,” a name also applied to 

any other palm used in the roofing of shelters, but 

in many cases the distinction is made by the addition of a prefix or qualifying word. In 1937, Cook 

TABLE 4.-Charactel-s known to be reliable in 

separating Coccothrinax from Thrinax 

Characters I Coccothrinax Thrinax 

Petiole .............. 

Fruit ..... .......... 

Seed , . .............. 

Endosperm .... 

solid in the sheath 

fleshy, purple-black 

cerebriform smooth 

infolded ruminate nonruminate, 

split in the sheath 

pulpy, white or ivory 

partially or completely intruded 

by the testa 

referred to a group of sturdy wind-resistant palms, 

including a Thrinax, as hurricane palms. Bailey 

(1938) referred to members of the genus as peaberry 

palms, and in 1949 he included members of 

Thrinax along with Coccothrinax under the name 

broom palms. 

1. Thrinax parviflora Swartz 

Thrinax parvipora Sw., Prodr. 57. 1788.-Ait., Hort. Kew. 

33473. l789.-Sw., F1. Ind. Occ. 1:614, t.13. 1797.-Linn., 

Sp. P1. sec. (Flrilld. ed.) 2:202. 1799.-Pers., Synops. P1. 

1:383. 1805.-Lam., Encycl. Mkth. 7:635. 1806.-Ait., Hort. 

Kew. 2nd ed. 2:307. 1811.-Titford, Hort. Bot. Amer. p. 

112. 1811.-Lunan, Hort. Jam. 2:28. 1814.-Pers., Synops. 

P1. (Diet. ed.) 2:1091. 1830.-Linn., Syst. Veg. sec. (J. A. 

& J. H. Schult. ed.) 7(2):1300. 1830.--Mart., Hist. Nat. 

Palm. 3:255, t.103, pro parte. 1838.-Kunth, Enum. P1. 

33253. 1841.-Griseb., F1. Brit. \t’. Ind. p. 515. 1864.-Cook, 

Bull. Torr. Bot. Club 28:535, pro parte. 1903.-Becc., 

Webbia 2251, pro parte. 1907; Annal. Roy. Bot. Gard. 

Calcutta (Martelli ed.) 13:327, pl. 28: fig. 3, pro parte. 

1933 [“1931”].-Read i?i Adams, F1. P1. Jam. pp. 75-76. 

1972. 

TYPE.--SWUT~Z s.n. Jamaica (a single sheet with 

juvenile leaf and packet of flowers). 

Small to medium palm, 1-10(-13) m high, caudex columnar, often very slender, 5-14(-15) cm in 

diameter, internodes 1.0-6.5 cm apart on lower 

trunk, reduced to lines above. 

Leaf sheath 45-70 cm long, apex long linguiforni 

7-22 cm long, netlike, entire, becoming ragged and 

fibrous with age, tan, velutinous, glabrescent with 

age on exposed surfaces; petiole (35-)50-145 (-160) 

cm long, abaxial surface densely tan lepidote, soon 

glabrescent on exposure, (1.0-) 1.2-2.2 (-2.4) cm 

wide at the sheath, (0.8-) 1.0-2.2 (-2.4) cm wide at 

apex; hastula triangular or rounded acute (0.1-) 

0.5-3.4 (-4.6) cm long, may become tubular with 

expansion and folding of blade, abaxially with a 

distinct ridge 0.1-0.5 (-1.0) cm long or a triangular 

projection 1.0-1.7 cm long; leaf in bud densely 

tan-brown lepidote on all exposed surfaces, often 

persistent on principal nerves and exposed portion 

of lower segments. 

Leaf blade when expanded very variable, circular 

and flat on young plants and in the shade, the basal 

lobes folded up away from the petiole when in the 

sun, and on older plants, or variously folded and 

contorted on tall slender plants, abaxial surface 

with microscopic widely scattered scales; palman 
70 ShIITHSOSIAPi CONTRIBUTIOSS TO BOTANY 

variously folded and very irregular in outline, 

(7-)8-34 (-42) cm broad; segments rhomboid (35-) 

37-57 (-60) in number, (38-)40-90 (-96) cm long, 

(2.3-) 2.8-6.0 (-6.4) cm wide, Jvidest beyond point ot 

fusion, the middle two or three segments a1tva)s 

fused for a greater length but rarely totally. 

Inflorescence erect to arching, 40-175 cm long, 

bracts greenish with brown appressed scales, each 

inflorescence with 7-22 primary branches, those in 

the lower half with 17-45 ultimate branches, these 

ivory to yellowish at antliesis, densely puberulous 

to glabrescent or glabrous, several of the loivermost 

branches occasionally forked or highly branched 

but subtended by a narrow triangular bract; flowers ivory to yellowish, fragrant, (lj-) 32-60 (-84) 

per branch; stamens 5-10 (-15) per flower, anthers 

linear to oblong (1.1-)1.2-4.0 (-4.2) mm long; infundibuliform stigma oblique to lateral, ciliate; 

developing ovary papillate to granulate. 

Fruit papillate to scurfy granulate, tan before 

maturation, become white and smooth or slightly 

punctate, except when infected by a fungus, then 

tessellated, 6.4-7.3 (-7.5) cm in diameter; pedicels 

bracteolate, (0.1-)0.5-2.8 (-5.2) mm long; primary 

branches yellow to orange at maturity of fruit 

(green or insect grazed at high elevations); rachis 

6-25 cm long; ultimate branches 4.5-17.0 cm long, 

1.1-1.5 mm thick at point of insertion on rachis; 

seed tan to dark brown 5.4-6.2 (-6.5) mm in diam., 

normally completely perforated by the testa. Haploid chromosome number, n= 18. 

TYPIFICATION OF Thrinax parviflora 

The original publication of Thyinax parvipora 

by Olof Swartz (1788) consisted of a very short 

diagnosis, which characterized the genus, and a 

reference to Patrick Browne’s account of the species 

published 32 years earlier. There was no reference 

to his own collections or to the younger Linnaeus’ 

unpublished manuscript. Patrick Browne’s (1756) 

description of the palm growing and thriving on 

all the rocky hills of Jamaica clearly indicated the 

palm intended. Swartz (1797) reproduced the 

Browne diagnosis and elaborated on it considerably 

with his own observations made while in Jamaica 

from 1784 to 1786. The description of such characters as long, glabrous, compressed-terete petioles 

which were longer than the 1-2-ft-long leaf blades, 

inflorescences shorter than the leaves and pale yellowish anthers leaves no doubt which Jamaican 

taxon was being described. Only one taxon in 

Jamaica exhibits these characters. An illustration 

in Sivartz (1797: pl. 13) shows dissections of the 

flower and fruit, but they are very schematic. The 

drawing unquestionably portrays Thyinax which, if 

interpreted on the basis of the scurfy-looking fruit, 

provides additional support for the present determination of the species. 

In the herbarium at the Naturhistoriska Riksmuseet in Stockholm, where many of Swartz’s collections are maintained, three herbarium specimens 

attributed to him have caused considerable confusion over the past 186 years. Through the courtesy of Professor Dr. Tycho Norlindh of the Riksmuseum, I was able to make a careful study of the 

specimens while they were on loan to Dr. H. E. 

Moore at the Liberty Hyde Bailey Hortorium, Cornell University, in New York. The three specimens 

represent two distinct taxa, both Jamaican, but it 

is obvious that only one of the sheets can be the 

type for Swartz’s Th7 ii2ax pnrviflora. The three 

specimens each have inscriptions in the hand of 

J. E. Wikstram, the director of the Botanical Nuseum and Botanical Garden of the Royal Academy 

of Sciences from 1818 to 1856. These inscriptions, 

according to correspondence betn.een Dr. E. Asplund of the Riksmuseum and Dr. L. H. Bailey in 

1937, “often giving valuable information regarding 

the provenience [sic] of the specimen, but sometimes being only a repetition of what is already 

present on the label (in old time mostly on the 

back of the sheet).” Each sheet has a quite different 

history and so will be discussed separately. 

The first specimen (Figure 46~) containing a 

short section of a Thrinnx inflorescence also contained a portion of a Bnctris inflorescence; the latter has been removed to another sheet. This sheet 

retaining the Thrinax specimen and labeled “Sabal 

umbraculifera illart.” could not have been collected 

by Swarti, for as Professor Norlindh has explained 

in correspondence: 

It once belonged to the Linnean Herbarium and can impossiblj ha\e been collected by Swaitz, who made his collection$ in the \Vest Indies in 1781-86. Di. Dahl obtained it 

fiom Linnaeus (patei), thus before 1778, and then it was 

incorpoiated in the herbarium of Baron Clas Alstromer and 

later left to the Ro!al Academy oE Science, the supeniser of 

Riksmuseum. 
SUMBER 19 71 

According to the letter from Asplund to Bailey, 

“Sabal umbraculifera Mart.” below the right specimen is 

written by TVikstrom. On the back of the sheet TVikstrom 

has repeated the same determination and also written “Herb. 

Alstroemeri”. In another hand is written “Palmeto Dahl.”, 

“Xorypha umbraculifera”, “Dahl a Linni- P.”, and “Jamaica”. 

Those words may be written by Clas Alstromer or Andreas 

Dahl (or perhaps by a copyist, since they are obviously written in text hand). After “umbraculifera” is added “Jacq.”, 

probably by W’ikstrom. The specimens on this sheet were 

given by Linnaeus to Dahl and came from him to Alstromer. 

Alstromer and Dahl were pupils of Linnaeus. . . . The former 

was a member of the Swedish aristocracy and had a botanical 

garden and museum in Gothenburg, of which he had employed Dahl as a keeper. His herbarium came to this museum 

in 1848. The father of Alstromer and Linnaeus were among 

the founders of the Royal Academy of Sciences.-There is 

nothing indicating that Swartz did ever see this specimen. 

The second specimen (Figure 46~) containing 

three pieces of a Thl-inax inflorescence, including a 

terminal portion with six primary branches attached, is labeled “No. 4 Sabal umbraculifera Mart. 

Jamaica Swartz” and “Herb. Swartzii” in Wikstrom’s hand. This and the preceding specimen 

belong to the same taxon, although probably not 

from the same source. It seems unlikely that, had 

either of these specimens been seen or utilized by 

Swartz, they would have been incorrectly labeled. 

The annotations by Wikstrom rvere made 40 to 60 

years after the publication of Th~innx by Swartz, 

FIGURE ‘%.-Two herbarium sheets often erroneously considered as part of the Swartz type for 

Thrinnx pnwi/lo~.n. Discussion in the text. (Supplied by courtesy of Prof. Korlindh, Riksmuseum, 

Stockholm.) 
ShfITHSONI.4S COiXTRIBUTIONS TO BOTAKY 

yet there is no indication that they ever were associated with the genus until Beccari annotated the 

sheets in 1907 and identified them with Thrinax. 

The third specimen (Figure 47) has a small flabellate leaf and a packet containing fragmentary 

rachillae and flowers. This specimen is labeled by 

Wikstrom as “Jamaica Swartz.” and “Thrinax parviflora Swz.” thus as early as the 1800s this specimen 

was recognized as one of Swartz’s own. In addition 

the packet contains flowers wrapped in paper labeled “Thrinax parviflora,” below which is written 

in a different hand, “Swartz scripsit.” The latter is 

no doubt Wikstrom’s handwriting for it is the same 

as on the other sheets. Thus Wikstrom provided us 

with the earliest indication of a specimen seen ancl 

perhaps even labeled by Swartz. 

In 1907, Beccari annotated all three sheets as 

“Spec. typ.!,” apparently not recognizing that two 

taxa were involved, also ignoring that only one of 

the sheets had been labeled Thrinax by Swartz. Dr. 

L. H. Bailey (1938:138), when writing about these 

same specimens, concluded, as has the present author, that the last sheet described (Figure 47) “undoubtedly may be considered authentic Thrinnx 

FIGURE 47.-Type specimen of Thrinax pamiflora 

Sw. preserved in the Riksmuseum, Stockholm, 

Sweden. Inset is a photomicrograph of one of the 

flowers in the packet on the type sheet (X ca 6). 

(Courtesy of Riksmuseum.) 
KUMBER 19 73 

TABLE 5.--Comparison of Swartz’s type and description of Thrinax parviflora 

with two of the Jamaican taxa 

Swartz type and 

Characters description 

Petiole length ................ 

Blade width .................... 

Pedicel length at 

an thesis ........................ 

Flower color ................... 

Anther length .................. 

’ longer than blade 

1-2 feet 

(0.5)0.7-1.5 (1.7) 

mm long 

yellowish 

(1.4)1.5-2.0 (2.2) 

Thrinax parvifiora 

subsp. paruipora 

longer than blade 

2-3 ft or more 

(0.3)O.j-1.5 (1.7) 

mm long 

ivory to pale yellow 

(1.1)1.2-2.0 (2.2) 

Thrinax radiata 

shorter than blade 

3-6 ft 

(1.4)1.6-2.4 (2.7) 

mm long 

white 

(1.7)l.a-2.3 (2.5) 

parvipora of Swartz.” Bailey had corresponded with 

both the Linnean Society of London and the herbarium of the Royal Botanic Gardens at Kew, in 

1937, but failed to turn up Swartzian Thvinax in 

either herbarium. 

An undated sheet containing an inflorescence of 

Thrinax located in the Banks herbarium of the 

British Museum was examined, at my request, by 

Dr. William T. Stearn, who made the following 

comments (in correspondence ) concerning Banks 

and Swartz: 

There is one sheet from Bank’s herbarium which Swartz 

almost certainly saw during his long period of work in London on his TVest Indian collections. If Banks already possessed a specimen from the FVest Indies, obviously, according 

to the attitude of the time, he did not need another, and the 

specimen he possessed was simply annotated with Swartz’s 

determination. If, on the other hand, Banks lacked a representative of the species, then Swartz gave him one and his 

specimen was mounted immediately and annotated according 

to Swartz, thus obviating error. Swartz did not mount his 

own specimens. He was a very generous man and evidently 

gave away many specimens. After his death his specimens 

were mounted at Stockholm and written up for the most 

part by Wikstrom; presumably Swartz had written the name 

on the covers, as was then usual with loose specimens, and 

presumably, as was also usual, alas! the covers were then 

thrown away. The sheet here collected in Jamaica by Robins 

was photographed by Moore in 1950 (this photograph B. hi. 

2577).18 In the capsule are two fruits presumably given to 

Banks by Swartz, as the sheet is annotated as having on it 

Jamaican material from “Dr. Swartz” and these fruits are 

the only ones to which this note could apply. 

l3 The specimen in the herbarium of the British Museum 

(Herbarium Banks) “Jamaica. Robins” has been chosen as 

the lectotype of Thrinax martii, as it is the only known 

specimen of those cited by Martius, upon which T. rnartii 

is based. 

There is no doubt now that the only specimen 

considered authentic Swartz material, and therefore 

the holotype, is the single sheet, illustrated in Fig 

ure 47, in the Riksrnuseurn in Stockholm, which 

has a small but complete leaf and a packet of 

flowers. The other two sheets, until now considered 

identical, are removed from the species and are 

treated under T. radiata. The Robins specimen in 

the Banksian herbarium also represents T. radiata, 

with the exception of the fruits which cannot at 

this time be placed with any certainty. 

In Jamaica there are three distinct and welldefined taxa in the genus Thrinax that have been 

recognized as a result of extensive field work and 

numerous collections. One of these must of course 

be associated with Thi-inax parvipora Sw. All three 

taxa have a 6-dentate perianth, an emarginate 

stigma, and a 1-seeded fruit. Apart from the information in the Flora, the type specimen provides 

additional evidence in support of the present determination of the species. The juvenile leaf on the 

sheet is unfortunately of little significance, although 

it has certain indefinable characteristics such a5 

texture and general appearance which suggest a 

similarity to the seedlings collected in the mountains. The leaf lacks lepitlia of any sort (T. 7-crdiata 

seedling-leaves usually exhibit scattered lepidia on 

the abaxial surface). The attached packet contains 

fragments of flowers and small pieces or rachillae, 

pedicels, and numerous anthers. Measurements of 

the anthers and pedicels are compared with similar 

measurements taken from plants at Devils Backbone 

and illorant Point in Figure 38. Although Swartz 

placed the genus in the Hexandria, flowers in the 

packet had as many as 7 stamen filaments still 

attached. Many flowers of Thrinax in Jamaica have 
74 ShlITHSONIAS CONTKIBUTIOSS TO ROTASY 

been found with 6 stamens; however, it is more 

common to find any number up to 12 or 15. 

Comparing the Swartz type and description with 

the taxa in Jamaica as presently understood, one 

taxon is immediately eliminated from consideration 

because two of the characters mentioned by Swartz 

in the Flora certainly do not apply. T1i)anax excelsa of the John Crow RIountains in eastern 

Jamaica has leaves no less than 6 to 12 feet across 

and very striking pink flowers. Another taxon, 

Thyinax 7 adiata, of littoral areas, has leaves ineasuring more than 3 feet across and the petioles are 

much shorter than the blade, the flowers are white 

and the floral pedicels are more than 1.6 niin long 

even at anthesis. Thus Thiinau Tadiatn, which has 

erroneously been knolvn as T. excelsa in Jamaica, 

T. ruendlandiana in Cuba, T. pnivipo7a in the Bahamas, and T. fioridnna in Florida, can also be 

ruled out. Recent anatomical findings agree. 

Although Thrinax paiuifloia Sw. is an extremely 

variable species (see section on variability) the 

population above 609 m (2000 ft) elevation on Mt. 

Diablo has been found to resemble S~vart7’s tj pe 

and description most closely. It is this population, 

seen on all the cliffs and rocky hills along the main 

route across Jainaica (now wbspecies pai~iflo~ u), 

which was chosen to represent one of the two 

Tamaican taxa in Table 5 comparing them with the 

Swartz material. 

In 1838, LIartius published an amplified account 

of T. pal-vifiora consisting of information from several sources. The description, including elements of 

several taxa, in fact appears to contain characteristics of his newly described T. muIt;floia. Grisebach’s description (1864) only contributed to the 

growing confusion concerning the application of 

T. parvifiora. 

For the first time in 199 years, identification of 

the species with a taxon in Jamaica came close 

when Beccari (1 907 ) recognized the Harris collection from Ferry River as true T. pa7-vifEo~a. Unfortunately, elements of a second taxon from the littoral of the north coast were also included in the 

description of the species. The illustrations of flowers and fruits that appeared in the 1933 supplement 

do not accurately depict authentic T. pni vipoia. 

On p1. 28: 111, figure 1 (taken from the Swart7 

type) and figures 2 and 4 (taken from a Harris 

specimen collected along Ferry River) represent 

true T. pnrvifloia, but the remaining figures most 

likely represent T. radiata. As a result, rather than 

straightening out the problem, Beccari further obscured the true nature of the species. In 1907, he 

also described T. tessellata based on a phytomorphic form from Mt. Diablo. Thrinnx haiyisinna 

described by Beccari (1908) was based on a nontessellated and immature-fruited specimen collected 

on the heights of Dolphin Head. 

Ilihen L. H. Bailey (1938) undertook the challenge to revise the genus, he did not fully understand T. pa~uifloia in Jamaica. Although Dr. Bailey 

collected and correctly identified material of authentic T. parvifiol-a from Salt River, Clarendon, 

and the Port Royal Mountains, in St. Andrew, he 

nevertheless chose to typify the species by using the 

Florida taxon. Although Florida and Jamaican 

plants of T. radiata differ only in minor quantitative characters such as leaf segment and fruit size, 

Diagnostic Key to the Subspecies of Thrinax parviflora 

1. Adasial hastular projcction 0.3-1.2 cni longx, lacking or vestigial abaxially: branches of the 

inflorescence glabrous, glabratc, or lightly; pubei-ulose; inflorescence crcct and shorter than 

the petioles at anthcsic; fresh anthers short (1.2-2.0 mm long): mature plants with leaves 

forming an open crown of conspicuously twisted and curled leaf segments ............ 

.............. ................. ....... wbspecies parvifZora 

2. Adaxial hastnlar projection \cry prominent or even long pointed, 1.5-4.4 cm long, prominent 

and up to 1.6 cm long abaxially; branches of the inflorescence densely granulose puberulose 

throughout; inflorescence arching, equaling or longer than the petioles at full anthesis; 

fresh anthers elongatc (ca. 2-4 mm long): mature plants generally with leaves forming a 

dense crown of broad blades with more or less flat to curved or slightly twisted leaf 

segments ...................................... subspecies puberula 

’* Measured from beneath the hastula, against the lamina. 
hUMBER 19 75 

it is curious that Bailey should have chosen those 

from Florida as representative of T. pnruipo.1-a while 

at the same time referring the Jamaican plants to 

T. excelsa. Specimens of true T. pawipom, which 

Bailey collected in Jamaica, were not considered 

in his final analysis. 

Following Bailey’s revision of the genus in 1938 

nearly all references to T. parvifiora that appear in 

the taxonomic literature actually refer to T. mdiata. 

Common Names: Sloane’s early common name 

for the species in 1696 was simply “thatch,” but in 

Patrick Browne’s description in 1756 the names 

“palmeto-royal” or ”palmeto-thatch” were cited 

L. H. Bailey cited “iron-thatch” as the common 

name on a specimen collected at Alligator Pond, in 

the Parish of Manchester, in 1931. Presently the 

species is called thatch, thatch-pole, or broom palm. 

Thrinax parviflora Swartz subsp. parviflora 

Thrinax earviflora Sw. subsp. paruiporn, I’rodr. 57. li88. 

[Type: Olof Su’artz, Jamaica (S).] 

Thrinax tessellata Becc., TVebbia 2:27l. 1907. [Type: W. X. 

Maxon & G. A‘. Collins 5, 26 May 1904. Hollymount, Jamaica, 2600 ft (792.4 m) elev. (B, specimen destroyed!; 

US, neotype, W. R. Maxon 2353).] 

Thrinax harrisiana Becc. in Fedde, Repert. 6:94. 1908. [Type: 

Harris 9273. Dolphin Head, Jamaica, 1500-1600 ft. (455.2- 

487.7) elev. (B, specimen destroyed?: UCIVI, isotype).] 

SPECIMENS EXAMINED AND COLLECTING LOCALITIES 

(Parish and locality number in Jamaica).-Abbreviations for herbaria are those of J. Lanjouw and 

F. A. StaAeu in Index Herbariorum, Reg. Veg. 31(1) 

ed. 5, 1964, with the addition of FTG, for the Fairchild Tropical Garden, Coral Gables, Florida, and 

DA, for L’gcole National d’hgriculture, Damien, 

Port-au-Prince, Haiti. 

Locality numbers correspond with those given 

on the map of Jamaica (Figure 48). 

ST. ANN 

5, Stirling Castle Forest Reserve: 609 m, Jan. 1958, R. A. 

Horvard 2 G. R. Proctor 15055 (GH, IJ); Jan. 1960, 

R. A. Hozc’nrd et al. 20513 (IJ). 

6. Lydford Post Office: 457.2 m, Dec. 1953, R. A. Horcard 

C- G. R. Proctor 13506 (BH). 

7. Deiils Backbone, 616.62 m, ridge along parish boundary 

east of Aft. Diablo: Jan. 1967, R. TI’. Read 1736, 1737, 

1738 (’3, CCT\’I, US). 

8. Union Hill: 669.96 m, Apr. 1908, A‘. L. Britton & 

A. Hollick 2753 (KY, US); Jan. 1967, R. 1%’. Rend 1939 

(BH, IJ, US). 

9. Grier Mount, 838.2-914 m: Dec. 1953, R. A. Howard 2 

G. R. Proctor I3611 (BH); Jan. 1966, X. Ti’, Rend 1573 

(US). 

ST. CATHERINE 

10. Hollymount Hill, 807.72 m, the first pinnacle on right 

side of Hollymount road after reaching 762 m elevation: 

-- 

ST. THOMAS 

J AMAlCA 

FIGURE 48.-Distribution of Thrinax parvipora in Jamaica. The locality numbers refer to list 

of Specimens Examined under treatment of the species. 
SMITHSONIAS CONTRIBUTIOSS TO BOTANY 76 

11. 

12. 

13. 

Apr. 1963, R. W. Read L- G. R. Proctor 1146 (FTG); Feb. 

1966, R. W. Read 1595,1596 (US); June 1966, R. TV. Read 

1681 (BH, IJ, S, UCWI, US); Jan. 1967, R. W. Read 1761 

(US); Mar. 1967, R. TV. Read 1835 L- 1836 (US). 

Hollymount: May 1903, TI’. R. Maxon 1961, 1962 (US); 

838.2 m, May 1904, LIT. R. Maxon & G. N. Collins no. 5 

(B, holotype of T. tessellata, not seen); May 1904, TV. R. 

Alaxon 2353 (UCM’I; US, neotype); Feb. 1905, TV. Harris 

no. 6 (UCIYI); Sept. 1906, A’. L. Britton 734 (NY); Aug. 

1931, L. H. Bailey 710 (BH). 

Blue Mountain, hft. Diablo, top of south escarpment: 

807.72 m, May 1967, R. W. Read 1895 (GH). 

Mt. Diablo: Mar. 1916, E. P. Kiilif, 420 (US); south slope; 

457.2-502.92 m, May 1967, R. TI’. Read 1896 (FTG); 

502.92-533.40 m, May 1967, R. IT. Read 1897 (FTG). 

14b. Charlton to IVorthy Park road: 27-mile marker, 487.68 

m, May 1967, R. TV. Read 1898 (US). 

27. 

30. 

31. 

32. 

MANCHESTER 

Somerset: 762-914 m, Feb. 1955, G. R. Proctor 11604 (IJ). 

TRELAWNY 

Ramgoat Cave: 457.2 m, Apr. 1963, R. TV. Read L- G. R. 

Proctor I148 (FTG); Nov. 1964, G. R. Proctor 25675 (IJ). 

Donkey Trail, ?,$ mile north of Burnt Hill intersection: 

518.16-556.26 m, May 1966, R. TI’. Read 1663 (US): Jane 

1967, R. W. Read 1757 (S), I758 (FTG). 

Burnt Hill: Jan. 1956, R. A. Howard et al. 14678 (IJ); 

1/4 mile north of intersection, 533.4 m, Apr. 1966, R. TI’. 

Read I640 (US). 

36b. TVeather Station (south of Windsor Cave): over 400 m 

elev., Apr. 1967, C. D. Adams s. n. (Read 1877) (US). 

ST. JAMFS 

37. Fray TVoods: 502.92-548.64 m, Mar. 1908, TV. Harris 10341 

(B, not seen; IJCIVI, US). 

HANOVFR 

38. Dolphin Head: above Askenish, 457.2-548.64 m, Mav 

1906, W. Harris 9273 (B, holotjpe of 7‘. harrisiana, not 

seen; UCWI, isotlpe); Mar. 1908, TI’. Harris 10264 (B, 

not seen; UCITI, US); Mar. 1908, A’. L. Britton L- A. 

Hollick 2217 (US); Feb. 1931, L. H. Bailey 15053 (BH); 

Sept. 1951, R. G. Robbins 2878 (UCM’I); Apr. 1955, G. R. 

Proctor 10054 (IJ); Mar. 1960, G. R. Proctor 2068? (IJ); 

Sept. 1960, C. D. Adams 7995 (M, UCIVI); Apr. 1963, 

R. TI’. Read L- G. R. Proctor I150 (FTG). 

39. Bubby Hill: 441.96 m, Aug. 1965, G. R. Proctor 26675 

41b. Hills near Kemshot: Mar. 1908, A’. L. Britton 2426 (US). 

(IJ). 

SOURCE UNKNOWN 

Olof Swartz, Jamaica (S, holotype of T. parviflora Sw.). 

Thrinax parviflora Swartz puberula, new subspecies 

A subspecie parviflora differt hastula adaxialiter 

1.5-4.4 cm longa et aliquantum prominente, abaxialiter usque ad 1.6 cm longa, inflorescentiae ramulis dense granuloso-puberulis. 

TYPE: R. W. Read 1565 Palmers Cross, Parish of 

Clarendon, Jamaica, Nov. 1965 (US). 

SPECIMENS EXAMINED AND COLLECTING LOCALITIES (Parish and locality number in Jamaica).- 

ST. ANDREW 

Cane River Gorge, 76.2-182.88 m: Mar. 1931, L. H. Bailey 

15089 (BH); Apr. 1963, R. W. Read 3 G. R. Proctor 1139, 

I140 (FTG); Mar. 1966, R. TV. Read 1603 (US). 

Dallas Mountain: Apr. 1963, R. TV. Read cb G. R. Proctor 

1141 (FTG); 542.54 m, Nov. 1965, R. TV. Read .b C. D. 

Adams 1559a (US). 

Long Motintain: Mona Hill, Sept. 1906, N. L. Britton 373 

(XY, US); vicinity of water tank, Montclair Dr., Beverly 

Hills, 213.36-243.84 m, May 1966, R. TY. Read 1657, 

1658c (BH, US); June 1967, R. W. Read 1950 (US); Mona 

Mt., May 1904, TV. R. Maxon 2147 (US). 

Ferry Hill: along river side, 30.48 m, May 1904, W. 

Harris 4 (B, not seen); Ferry River, G. A’. Collins s. n. 

(US): May 1904, TV. R. Mavon 2190 j. 2197 (US). 

ST. CATHERINE 

14a. Charlton to ‘/%‘orthy Park road (26-mile marker): 381 

m, June 1966, R. TV. Read 1672 (FTG). 

14b. Charlton to W‘orthy Park road (26.5-mile marker): 

487.68 m, June 1967, R. TV. Read 1941, 1944 (US). 

15. Mendez Hill to Spring Vale: 152.4-304.8 m, May 1967, 

R. W. Read 1899 (FTG), 1900 (NY). 

16. Cudjoe Hill: 152.4 m, Mar. 1966, R. W. Read 1602 (BH). 

17a. Johnston Pen vicinity, near rock quarry, 2-4 miles 

south from Spanish Town, off the Friendship Rd.: 121.92 

m, Nov. 1969, R. TI’. Read 1655a, 1655b (US). 

17b. Guanaboa Vale, 9 miles NLT of Spanish Town: Nov. 

1965, R. TI’. Read 1551 (US). 

18. Spiing Garden: 76.2 m, Mar. 1966, R. II’. Read 1600, 

I601 (BH). 

19. Hellshire (Healthshire) Hills: near Salt Island, 76.2 m, 

Sept. 1908, IT. Harris ~9 S. L. Biitton 10524 (UCWI, US). 

20a. Rio Cobre Gorge: near Bog Walk, ca 182.88 m, Feb. 

1931, L. H. Bailey 15065 (BH). 

20b. Great Goat Island: Apr. 1920, TT’. R. Maxon 3 E. P. 

Killip 1593 (US). 

CLARENDO~ 

21. Palmeis Cross: in a sisal field, 45.72 m, Apr. 1963, R. 14’. 

Read 3 G. R. Pioctor 1147 (FTG); Sov. 1965, R. W. 

Read 1565 (BH, S, CTCFI’I, US, holotjpe of 7’. parviflora 

subspecies ~iubeit~la); June 1966, R. TI’. Read 1676b (BH, 

s, UCWI, US). 
NUMBER 19 77 

22. 

23. 

24. 

25. 

26. 

28. 

29. 

31. 

33. 

34. 

35. 

36. 

40. 

41a 

42. 

Cockpit: 4.75-12.19 m, June 1966, R. W. Read 1675a, 

16756 (US); Feb. 1967, R. W. Read 1827b (US). 

Salt River: ca 15.24 m, Nov. 1935, I.. H. Bailey 202 (BH). 

Portland Point: 3.05-6.1 m, Feb. 1967, R. W. Read 1825 

Clarendon Park: 83.82 m, Feb. 1966, R. IV Read 1583 

(US). 

(BH). 

MANCHESTER 

Round Hill: 60.96 m, July 1966, K. 14’. Read 1689 (US). 

Alligator Pond: Feb. 1931, L. H. Bailey 15080 (BH). 

ST. ELIZABETH 

Bull Savanna: 152.4 m, July 1962, 

(UCWI). 

TRELAWNY 

White Bay: 3.05 m, Aug. 1966, R. 

(US). 

E. T. Robertson 9326 

14’. Read 1702a, 170211 

Donkey Trail, y2 mile north of Burnt Hill intersection: 

518.16-556.26 m, May 1967, R. Ti’. Read 1946 (US). 

Mango Tree Hill (Carambi Hill): 542.54-563.88 m, Jan. 

1966, R. W. Read 1574 (US); May 1966, R. TI’. Rend 1662 

Sherwood Content: 228.6-247.32 m, Oct. 1955, G. R. 

Proctor 11065 (IJ). 

Mt. Pantrepant: ca. 91.44 m, Nov. 1935, L. H. Bailey 215 

IVindsor Cave: 152.4 m, Aug. 1955, G. R. Proctor 10540, 

15631 (IJ). 

(US). 

(BH). 

HANOVER 

Silrer Spring: near Fish Riler, 60.96 m, Mar. 1966, R. TI’. 

Read k Iwor Corninan 1614 (K). 

Lances Bay: 15.24 m, June 1966, R. 1%’. Read I669 (S). 

WESTMORELAKD 

h’egril Hill: New Hope Estate, 53.34-76.2 m, Nov. 1955, 

G. R. Proctor 11206 (IJ); inland from Revival, June 1966, 

R. W. Read I670 (US). 

SOURCE UNKNOWN 

1849 TVulZschZageZ 8573 “Borassus flabelliformis L.?” (M); 

1878 W. 1512, 2 sheets (UCWI). 

2. Thrinax radiata Lodd. ex J. A. & J. H. Schult. 

Thiinax radiata Lodd. ex J. A. & J. H. Schult. in Linn. 

Sjst. Veg. sec. 7(2):1301. 1830.-Mart., Hist. Nat. Palm. 

3:257. 1838.-Kunth, Enum. P1. 3:253. 1841.-Becc., Annal. 

Roy. Bot. Gard, Calcutta (Martelli ed.) 13:335. 1933 [“1931”]. 

[Type: Specimen in Herbarium Regium Monacense “e horto 

paris” (M).] 

Coccothrinax radiata (Lodd. ex J. .4. & J. H. Schult.) Sarg. 

ex K. Schum. in Just’s Bot Jahresb. 27 (1):469. 1901. [4s to 

the type only, not subsequent usage and associations.] 

Thrinax floridana Sarg., Bot. Gaz. 27:84. 1899; Silva 14:81, 

t. 735. 1902.-Small, F1. S.E. U.S. p. 221. 1903.-Becc., 

TZ‘ebbia 2:262. 1907.-Small, F1. Fla. Keys p. 26. 1913.- 

Sarg., Manual Trees N. .4mer. p. 97. 1926.-Becc., Annal. 

Roy. Bot. Gard., Calcutta (Martelli ed.) 13:328. 1933 

[“1931”].-Read, Amer. Hort. Mag. (Ledin ed.) 40:28. 

1961.-Read in Moore, Principes 7:168. 1963. [Type: 

Sargent, Thrinax no. 2, 14 R’ov. 1898 (“cultivated at Miami 

from Long Key”), Florida (AAH).] 

T. zoeizdlandiana Becc., W‘ebbia 2:265. 1907. nom. illeg.? 

Pomona Col. Journ. Econ. Bot. 3:403, f. 168. 1913.-Sarg., 

Manual Trees N. .4mer. p. 97. 1926.-Burret, Sv. Vet-akad. 

Handl. ser. 3, S(7):lO. 1929.-Becc., Annal. Roy. Bot. Gard., 

Calcutta (Martelli ed.) 13:332. 1933 [“1931”].-Lebn, F1. 

Cuba. 1:260. 1946. [Type: Tl’riglit no. 3219 (1860-1864), 

Cuba (G).] 

T. martii Griseb. et H. I\’endl. ex Griseb., Cat. P1. Cub. p. 

221, 1866 [excluding elements of Coccotlirinax]. [Type: 

Jamaica. Robins (Inflor.) Herb. Banks (BM).] 

T. putnilio sensu Mart., Hist. h’at. Palm. 3:256, as to tab. 

103, f. IV, 1-4. 1838 [et auct. non Lodd. ex J. A. pi J. H. 

Schult. in Linn. Syst. Veg. sec. 7(2):1301. 18301. 

Porothrinax puiiiilio H. TVentll. ex Griseb., Cat. P1. Cub. p. 

221. 1866 [pro parte, as to the specimen cited, not the type]. 

T. parni/?ora auct. non Sw.: Mart., Hist. Sat. Palm. 332.55, 

pro parte. 1838.--Sanv., Anal. Acad. Ci. Habana 7:563. 

1871.-Vasey, Cat. For. Trees US., USDA Rept. no. 11. 

1873:186. 1876.-Chapm., Bot. Gaz. 3:12. 1878; F1. South. 

U.S. p. 651. 1883.-Sarg., Gartl. & For. 9:162. 1896.-Becc., 

ITebhia 2:25.5, pro parte. 1907,- Small, Journ. N. Y. Bot. 

Gard. 26:49. 1925; 31:58. 1930; Sci. Monthly 32:242. 1931.- 

Becc., Annal. Roy. Bot. Gard., Calcutta (Martelli ed.) 13: 

327, pro parte. 1933 ~’1931”].-Small, Manual S. E. Flora 

p. 241. 1933.-Bailey, Gent. Herb. 43135. 1938.--Buswell, 

U. of Miami Bull. 19(6):49. 1945.-Bailey, Gent. Herb. 8: 

991. 1949.-Bomhard, U. S. Dept. Agric. Inf. Bull. no. 22, 

p. 21. 1950.-Asprey & Lor-eless, Journ. Ecology 46:547-570. 

1958.-Alain, Principes 5:68. 1961.-Long pi Lakela, F1. 

Trop. Florida p. 245. 1971. 

T. excelsa sensii Bailey, Gent. Herb. 4:134. 1938 [non Lodd. 

ex Griseb., F1. Brit. IV. Ind. p. 515. 18641. 

T. nzultiflora sensu Read in Adams, F1. P1. Jam. p. 76. 1972 

[non Mart., Hist. Nat. Palm. 33255, t. 103, f.l.a., t. 163. 18381. 

Medium palm, (1.5-)2.0-10.0 (-12.0) m tall, 

caudex columnar, 8.1-1 1.6 (-13.0) ern in diameter, 

tapering out to an enlarged base and mound of 

roots, internodes 4-7 ern apart on lower trunk. 

Leaf sheath 58.4-62.2 ern long, apex oblique 

down from petiole, tearing away from petiole and 

soon becoming coarsely fibrous, indumentum persistent on fibers; petiole 36-94 ern long, adaxially 

flat to slightly convex, 2.2-3.1 cm wide at sheath, 

rounded abaxially, 1.6-2.3 cm wide at narrowest 

and 2.1-3.2 ern wide at apex, abaxially with scattered scales, soon glabrescent or with few persistent 
78 SMITHSONIAN COSTRIBUTIONS TO BOTANY 

scales; hastula acuminate or sharply triangular, 1 .O1.9 cm long, often tending to decurve or split with 

the expansion of the blade, abaxially a short (0.1- 

0.4 cm long, flap or ridge, often with one or two 

rounded or toothlike prominences; unopened blade 

glabrescent on the adaxial nerves, scattered floccose scales on abaxial nerves and exposed surfaces. 

Leaf blade, when expanded, circular in outline, 

1.2-1.6 m in diameter, abaxial surface lighter in 

color than adaxial surface, abaxially dull, often 

glaucescent, flecked with conspicuous gray lepidia, 

zone around hastula yellow green, translucent when 

viewed from below against the light; principal 

nerves yellow green; palman 30-55 cm broad, relatively flat or slightly folded; segments 51-63 in 

number, narrowly trullate, often acuminate, with 

long slender apical filaments which are readily 

lost, (73-)79-113 (-1 15) cm long, (4.6-)5.1-6.2 

(-6.4) cm wide, widest at sinus or rarely slightly 

above; fusion 30-55 cm long in palman, relatively 

uniform throughout blade, but gradually longer 

toward upper middle; center tJvo segments near 

apex of blade often fused throughout their length, 

basal segments commonly overlapping. 

Inflorescence erect, or arching slightly at anthesis, 

1.2-2.2 m long, bracts green, with white or gray 

scales, 13-2 1 glabrous primary branches, the lowermost primary branches with (24-)27-37 ultimate 

branches, these white at anthesis, tip to 12 cm long; 

pedicels at anthesis (1.4-) 1.6-2.3 (-2.7) mm long; 

flowers white, fragrant, 46-56 per branch; stamens 

(5-)6-8 (-10) in number, anthers linear (2.0-)2.2- 

8.5 (-3.6) nim long when fresh, (1.7-)1.8-2.3 (-2.5) 

mm long when dry, filaments very narrowly connate 

basally, angle of connation acute or rounded. 

Fruit 7.0-8.2 mm in diameter smooth, ivhite at 

fresh maturity, green and slightly papillate shortly 

before; seed light brown 6.0-6.8 mm in diameter 

completely perforated; primary branches yello.izish 

green at fruit maturity, pedicels (1.2-)2.0-5.0 (-5.2) 

mm long. Haploid chromosome number, n= 18. 

SPECIMENS Ex.z-\rrsFD.-J.ARi.L\IC..I. ST. THOW~~. RfOmnt 

Point along the road to the lighthouse, on limestone near 

It‘hite Bay: Mar. 19.54, G. R. Proctor 8393 (11); Aug. 1955, 

G. R. Prtoctor 10413 (IJ); Aug. 19.54, G. Tl’ehster & K. Wilson 

5236 (IJ); Apr. 1963, R. TT’. Read L- G. R. Proctor 1142, 1143, 

I144 (FTG); Feh. 1967, R. IT’. Rend 1791 (BH, US); July 

1967, R. TI‘. Read 1959, 1960, 1961, 1962 (IJ, UCTVI, US). 

Holland Bay: 1952, G. I;. Asprey 2879 (UCTVI), ST. ~I.\RY. 

Galina Point on dry coastal limestone, forming a woodland: 

date unknown, G. R. Proctor 15546 (IJ); Apr. 1956, TV. T. 

Stearn 775 (BH, UCTt’I); .4pr. 1956, A. R. Loveless 2879A 

(LCT\’I): without date, Collins 153 (US). Crab Tt’oods, west 

of Galina: Xov. 1965, R. 15’. Read 1553 3 1554 (US). ST. 

.ANs. Queen’s Highway between Discovery Bay and Bengal 

Bridge: Aug. 1935, G. R. Proctor 10568 (IJ); Feb. 1957, G. R. 

Proctor I6152 (IJ). St. Ann’s na!: Feb. 1931, L. H. Bailey 

15058 (BH). TRELAWKY. Near Salt Marsh on sea side of 

road: Apr. 1963, R. W. Read 1149 (FTG). HANOVER. \Test of 

Lucea near the sea: Apr. 1963, R. 14’. Read 1151 (FTG). 

Rutlands Pen, near Bloody Bay: Mar. 1966, R. Ti.. Read 1611 

(us). ~t’rST3fOREI.AND. Near Negril Lighthouse: Nov. 1953, 

G. R. Proctor 11132 (IJ). Negril, on rocks near the sea: 

Mar. 1962, C. D. Adoms 1097s (CCTt’I). ST. ELIZABI’TH. Long 

Acre Point, west of Black River: Sept. 1907, TI’. Harris 9957 

(ITCII’I, US). Loczrnu U~~KSOIYK. “,7nninicn. Robitis” s. n. 

@%hi, lectotype of T. innrtii Griseb. ct H. Td’endl. ex Griseb.). 

H.AITI. LA GoNxvr. Pointe Latanier: Aug. 1927, E. L. 

Emrm H. 8841 (D.4, IJ, S); “E troite”: Aug. 1927, TI’. J. 

Eye~dnn7 292 (:IS), DEPT. DU SCD. Massif de la Hotte: western 

gronp, Les Roseans, Oct. 1928, E. I.. Ekninn H. 10782 (S). 

CUB.4. PROV. PINAR DFL Rro. Sear Sahalo: Soy. 1920, E. 1,. 

Eknizln 11443 (S). Las Pozas: Apr. 1934, G. Saleson for Ledn 

16102 (BH). PROV. HARANA. Vedado: 1929. Brother Ledn 

14191 (BH). Bataban6: Nov. 1904, J’nn Herniann 3928 (NY, 

ITS), Playa dc Marianao: Feb. 1910, S. L. Britto77 2 P. Ti’ilson 

4557 (US); Mar, 1929, I-. H. Bailey I2529 (BH). RIanano (?): 

scattered on high sand dunes, July 190.5, J’nn Hermaniz 898 

(NY, LS). PROV. CAMAGCEY. Cayo Gnajaha: Nov. 1909, J. A. 

.Shnfer 284 6 (US). PROY. LAS Vr1.1.~~. Punta Diahlo, Cienfuegos 

Bay: Mar. 1910, S. I.. Britton L- P. TI’ilson 6044 (US). PROV. 

ORIESTE. Punta tle hlaisi: Mar. 1931, L. H. Baiiey 15145 

(BH); Oct. 1934, Herinnno Ledn 16192 (BH). Manati: June 

1932, Herniniio Ledx 15670 (BH). North of “Raimon,” Nipe 

Bay: May 1909, I. A. Shafer 1785 (US). “In Cuba Orientali, 

1859, 1860”: C. Wright 2329 (AAH, GH, NY, US, syntypes 

of T. rclendlondinna); 1860-1861, C. Ti’right 3219 (G, lectoty’e of T. zi’enrlla~zdiona, F, CH, K, isotypes). Vicinity of 

P[B]aracoa: Feb. 1902, C. I.. Pollard, E. Poliner 3 It’. Palmer 

192 (US). ISIA DE PINOS. Boqueron, Ensenada de Siguanea: 

Feb. 1916, S. I.. Bt-itton, P. T4’ilson &- A. D. Selby 14491 

(US). Playa Bibijagua: Feb. 1956, E. P. Killip 45604 (US). 

Downs of Progreso: Dec. 186.5, Schott 

293 (US); (without date), G. F. Gnu,,ier 1100 (NY, U‘3); May 

19,52, H. E. Moore 6366 (BH). Santa Clara: 1959, S. Kiem 329 

(BH). Izamal: hiar. 1916, G. I;. Gntciner & So77s 23317 (NY, 

US); Rlar. 1916, G. F. Gaictner L- Sons 23265 (NY). QUISTANA 

Roo. Puerto Juarez, sand dunes beside sea opposite Isla 

Mujer: Oct. 1959, H. E. dloore 8086 (BH). 

CESTR.AL AMERICA. COUNTRY UNKSOWS. 1886, G. F. 

Gaunier s. n. (US). BRITISH HONDURAS. All pines: Aug. 1930, 

TI’. A. Schipp 661 (NY), Belize District: hiile 29 Cayo Road, 

May 1960, S. Kieni 605 (BH). HONDI‘RU. Forest near Bolet’s 

plantation: Feb. 1903. P. Wilson 360 (NY). 

FLORIDA. DADE COUNTY. “Cultivated at Miami from Long 

Key”: SOY. 1898, C. S. Snrgent no. 2 (.-IAH, holotype of 7. 

floridnnn); So\-. 1898, C. .S. Sargent 202 (NY). Miami, cult. 
KLMBER 19 79 

from Keys: 0ct.-Nov. 1901, J. K. Small 5 G. V. Sash 347 

(NY, US). COLLIER COUNTY. Cape Romano: May 1898, C. S. 

Sargent s. n. (AAH). Caximbas Island: Apr. 1892, J. H. Simpson 180 (NY). Cape Sable: Oct. 1858, A. P. Gnrber 43 (NY, 

US). Northwest Cape: Apr. 1916, J. K. Suiall 7699 (NY, CS). 

MONROE Couvru. Sands Key: Xiar. 1904, N. L. Britton 344 

(NY). Elliott Key: (cult. at Little River, Miami), Apr. 1932, 

0. F. Cook s. n. (US). Key Largo: Jan. 1909, J. K. Small AJ. J. Carter 2953 (NY). Lower Rlatccutnbe Key: .ipr. 1932, 

0. F. Cooke 3 J. T. Presley s. n. (US). Long Key: Jan. 1963, 

R. TV. Rend 799 (US). Grassy Key: Feb. 1937, E. P. Killil, 

32109 (US). Vacca Key: Jan. 1909, J. K. Smnll L J. J. Carter 

2959 (91’). Boot Key: Apr. 1909, S. L. Britton 542 (NY). 

Big Pinc Key: Jan. 1952, E. P. Kiilil, flSf2 (US). Torch Key: 

May 1890, A. H. Curtiss s. n. (AAH). TVater Key: .ipr. 1932, 

0. F. Cook L- J. T. Presley s. n. (SSC, SY, US). Racoon Key: 

Mar. 1898, C. L. Pollard, G. S. Collins L- E. I-. Morris 101 

(SY, US). Stock Island: Nov. 1955, E. P. Killip 45097 (US). 

Area Unknown: Hammock, May 1917, F. TV. Pelinell 9617 

(US); Sykes Hammock, Sept. 1929, H. O’Seill s. 11. (US). 

BAH.4hf.G: Cat Cay, May 1905, L. J. K. Bruce 3753 (US). 

SOURCE UKKNOIVK: Specimen in Herbarium Regiunl 

Alonncetzse “E Iiorto . . , kuris” (RI, holotype of T. radiata). 

DIscussIox.-The name Thrinax mdiatn is the 

second oldest binomial published in the genus 

Thrinax. Having first been published by Renato 

Desfontaines (1829) ivithout a description (but 

with a reference to Martius’ unpublished work), the 

name therefore had no botanical standing. The following year, however, the father and son team of 

J. A. and J. H. Schultes took up the name but 

cited Loddiges, the English nurseryman, instead of 

Desfontaines as the earlier source of the name. 

Their short diagnosis, based solely on a small leaf, 

also included a reference to “Martius in litt.” and 

Desfontaines’ “Cat. h. paris.” Among the specimens 

of the Herbarium Regium Monacense at Munich is 

a specimen of a juvenile leaf labeled “Thiinax 

mdiata Lodd. E. liorto . . . paris” (Figure 50), .Izhich 

is undoubtedly the one described and indicated in 

the Schultes publication as Thrinax radintn. No 

specimens were cited by either Martius or the 

Schultes team, but the reference to Rlartius and the 

original diagnosis pertaining to a juvenile leaf 

clearly indicate the specimen at Munich. A specimen of an inflorescence studied by Lehn in 1939 at 

Paris (Herbario de Houllet) could not have been 

seen at the time of the original publication, since 

no mention of an inflorescence was made in the 

original diagnosis. The specimen at hIunicli, which 

I am designating as liolotype, measuring 25 cm 

a Coccothrinax on sight; however, it was not possible until this past year to ascertain exactly its specific identity. Beccari had annotated the specimen 

as “TIi1iiinx ponceana 0. F. Cook?’ but did no 

more. FolloJving a thorough study of the laminar 

anatomy of all four species of Tliiinax, their various biotypes and juvenile plants, it is now possible 

with known materials to identify unquestionably 

the true specific identity of the t)pe specimen of 

T. uidiata. 

Eight years following the publication by the 

Schultes team, Martius’ publication (1838) apFILVRF 49.-.i primary branch of the fruiting cluster with 

across, appears certainly to be either a Thiinrtx or nearly mature fruits of Thrinax radiatn. 
80 SMITHSONIAX CONTRIBUTIONS TO BOTANY 

peared with but little more to aid in the disposition 

of the name. The name Thrinax radiata appeared 

in Grisebach (1866) and again in Sauvalle (1871) 

but with no indication concerning its application 

in Cuba. Drude (1887) treated Thrinax mdiata in 

his subgenus ‘‘I Eu-Thrinax” along with T. paiuiflora and T. multiflora. The subgenus was erected 

on the basis of seeds, but since no seeds of the 

original collection are known and no mention of 

seeds or fruits appeared in the original description, 

it is surprising to find T. radiata so treated. 

The next significant publication concerning 

Thrinax radiata appeared when Sargent (1899) 

FIGURE 50.-The type specimen of Thrinnx yadiata from the 

Herbarium Regium Rlonacense, Munich. 

created the new segregate genus Coccothrinax. For 

no indicated reason Sargent (p. 89) stated simply 

that, “Thrinax argentea R. & S.; Thrinax radiata 

R. & S.;” also “belong in Coccothrinax.” Perhaps 

he was aware of another specimen of Coccothrinax 

flowers which has apparently been erroneously associated with the T. radiata type specimen. It remained for K. Schumann (1901) to make the 

correct combination in that genus. In 1933, Beccari 

treated the name as an “Imperfectly known or 

doubtful species.” In 1939, Brother Leh, apparently unaware of the earlier transfer, published the 

“new combination” and elaborated on the original 

diagnosis with information from the specimen he 

had studied in Paris. 

It is obvious that the description of Thyinax 

pal uiflol-a, which appeared in Martius (1838), contains several elements not applicable to the Swartz 

concept. Grisebach (1866) recognized this when he 

published T. maytii based on “T. pawifioia Mart. 

non Sw.” Martius’ literature citations apply to T. 

paruiflora Swartz, but references to the leaves being 

“subtus parce floccosocanescentibus” (p. 225) and 

“Indumentum in pagina laminae inferiore parcum, 

e floccis albis decumbentibus constans” (p. 256) 

quite likely refer to Coccothrinax. The major portion of the description, however, applies to Thrinax, 

probably T. mdiata. The locality citation: “Crecit 

in insula Jamaica, praesertim orientali, colles saxosos praediligens, nec tamen a locis depressis maritimis exulans,” clearly indicates T. radiata, as does 

pl. 103 (the inflorescence to the left). This illustration corresponds amazingly well with the Robins’ 

Jamaica specimen “spadices floridos in herbariis . . . 

et Banksiano asservatos” (p. 255 ) from which 

much of Martius’ description was clerived. 

Since Thyinax martii (Griseb. & Tliendl. was 

based primarily on the description and illustration 

by Martius (1838), and the “Jamaica Robins” specimen is the only one in the Banks herbarium which 

could represent the material used by Martius, it 

seems logical and in the best interest of nomenclatural stability to select that specimen as lectotype. 

In 1907, Beccari founded a new species, Thyinax 

wendlandiana, partly based on collections made by 

Charles Wright in Cuba. A specimen in the Geneva 

Herbarium labeled “Plantae Cubensis Wrightianae 

KO. 3219, coll. C. Wright, 1860-1864” was annotated by Beccari in 1907 with a note stating that 
NUhlBEK 19 81 

iliright’s number 3219 was used in support of 

“Porothrinax pumilio (fructus) , , . Thrinax Rlartii 

(flores) . . . Thrinax argentea Mart. (folium) Griseb. 

Cat. Cub. p. 221.” This sheet has an annotation 

label identifying it as “Thrinax wendlandiana 

Becc.” and has also been labeled “T~~LIs” but I am 

not certain by whom. Th~is he further contributed 

to an already confusing nomenclatural mess. 

Although Beccari cited “Thrinax Martii Gris. et 

Wendl. in Gris . . , (pro parte?)” for Coccothrinax 

martii Becc., he seems to have treated “Th. Martii 

Gris. et Wendl.” in its entirety under T. wendlandiana. Therefore under the rules of priority Beccari 

should have taken up the epithet “martii” instead 

14The Wright specimens are a source of considerable confusion, partly because some of the specimens have the same 

number, with a series of letters. These specimens must be 

examined at length and independently in order to determine 

their correct identity. 

of using T. wendlandiana. All the Wright material 

cited under number 3219 has so far represented but 

a single taxon of Thrinax. It appears that Beccari 

(pp. 268 and 308) was separating out what he considered Thrinax elements under T. wendlandiana 

and referring the epithet to the genus Coccothrinax. 

It is obvious, however, from a study of the specimens cited, and lectotypified by Wright No. 3219, 

that T. wendlandiana is conspecific with T. radiata. 

Vasey (1876) reported a palm from Florida, which 

he called Tlarinax parviflora. A. W. Chapman 

(1878) confirmed this report when he reported the 

occurrence of the palm on the “Keys along the 

Florida Reef, extending up the west coast as far as 

Cape Romano.” When Sargent (1896) published 

his first palm study he too used the name T. parviflora. The illustration (pl. 510) published at the 

same time depicted the inflorescence and fruit of 

what is presently known as Coccothrinnx argentata, 

FIGURE 5l.-Thrinnx radiatn at Morant Point, Jamaica: A, leaf blade showing the broad flat 

palman, hastular region, and overlapping lower segments; B, plant with inflorescences in fruit 

with seberal new ones emerging from the crown. 
82 SSIITHSONIAN CONTRIBUTIONS TO BOTANY 

FIGURE 52.--Thvinnx rndiata in natural habitat on thc Florida Kejs. 
NUMBER 19 83 

with a leaf of Thiinax in the background. Sargent 

(1899) later became convinced that the palm in 

Florida was not T. parvipoia Sw., “but distinct 

from that species, as collected by Charles iVright 

in Cuba (no. 2329) and determined by H. TVendland.” He therefore published a new binomial, T. 

floridam, based on its having “longer and stouter 

fruiting pedicels, smaller fruit and deeper seminal 

cavity.” This new name again appeared in his 

revised palm study (1902), along with an illustration (fig. 735) clearly depicting tlie palm natile to 

Florida. 

Beccari accepted Sargent’s new species and included it in his 1907 publication. It is important 

to note here that two names, which in the present 

study are considered synonjnious, appeared in Keccari’s key separated from one another and from 

T. pa~uifiot-a by the use of such characters as 

perianth-lobe form, anther length, fruit, and seed 

size. Several noncomparative quantitative chaiacters were also mentioned. As Small (1925) pointed 

out, “the diagnostic characters on record for the 

distinguishing of the two supposed species-Tlzi 2nax 

pot idan(i and T. T.T’eiidlnndiann-in Florida, may 

be found on the same plant.” Beccari (1933) elen 

went so far as to state that his T. iuendlandznna 

also occurred in southern Florida at hladeira Hummock and at Pumpkin Key. 

In 1925, Small wrote that, “judging from recent 

information and study,” the Florida taxon “proves 

to be the same as Tlwinax paivifloin of the TVest 

Indies.” Thus coming full circle to the original 

incorrect determination by Vasey half a century 

earlier. Although Small had not arrived at the correct conclusion concerning the name of the taxon, 

he had, however, concluded that the reason for the 

confusion lay in the fact that “decisions were based 

on too scanty material, where ample specimens 

should haxe been or could have been secured”; and, 

“secondl), the main studies were made in the closet 

instead of in the field.” 

When Bailey (1938) published his study of 

Thyinax, he followed Small’s application of T. 

pclJ7lipOJN. Although Baile) used the incorrect 

name, he was the first to recogniie that the palms 

collected and described under various names from 

the littoral of Haiti, Jamaica, Cuba, Florida, The 

Bahamas, LIexico, and Bri tish Honduras were members of a single taxon. TVhen Bailey examined the 

three specimens of “Thiinau pnivipmn” in the collection of tlie Stockholm herbarium, he believed 

them to represent a single taxon; however, he selected one sheet about which he stated: “That 

sheet undoubtedly may be considered authentic 

Thrinax pa~uzfloi a of Swartz.” It was unfortunate 

that he chose to draw his information and characterization of that species from an altogether different sheet, for the sheet Bailey chose (1938: fig. 81) 

contained a large portion of an inflorescence (figure 45~) which was labeled as “Sabal uinbraculifera” as recently as 1907. (See discussion of S~varti’ 

type and typification under T. paivipoi a. 

Bailey’s key (1938) to the species of Thiznnx 

utili7etl quantitative characters such as siie of fruit 

and leaf segments, and differences in the diied epidermis of the fully developed but not nccessarily 

“mature” fruit. The so-called differences in the 

abaxial surface of the leaf vary on a single plant 

depending on the age of the leaf selected. The 

hastula was mentioned in support of “T. paivzpoia” 

and the “spathelets” were mentioned in support of 

“T. excelsa,” but they are not reciprocally compared. Thyinax indintn, although distributed over 

1000 miles across the northern Caribbean and on 

many different islands, varies slightly in quantitati\ e characters but maintains its peculiar individuality as a single species. 41though Baile) found no 

appreciable differences between the Florida plants 

and those of Cuba, Haiti, and Central America, he 

nevertheless selected a plant collected by Britton 

in coastal thickets of Jamaica as typical of T. excelsn. 

At the turn of the century misconceptions and 

confusion regarding Th~inax pervaded every attempt to revise the genus. Britton collected Thi inax 

indzatn in both the Bahamas and Jamaica, and 

identified the plants as T. parviporn, although he 

(1908) stated that Tl71217nx excelsn “from Jamaica, 

is abundant on that island and distinct from T. 

pa?v~floin, to nliich it is doubtfully ieferred b) 

Beccaii.” It is difficult to know what plants were 

considered T. exrplcn b) Britton, for his specimens 

from Morant Point, Jamaica, were identified as 

T. pnivipoia, and the specimens from the John 

Crow hIountains formed the t) pe of his new species 

lsVarying reports of the color of the abasial leaf surface 

seem to stem from different impressions and the use of vague 

descriptivc terminology such as “indifferently lighter colored,” 

“whitish or silvery,” “glaucous or whitish,” “silvery-lvhite,” 

all of which havc at one time or another been applied to 

the Florida taxon. 
84 SMITHSONIAN COSTRIBUTIONS TO BOTANY 

T. rex. Bailey accepted Britton’s identification of 

the Bahamian material but referred the Jamaican 

collections to T. excelsn. Bailey was unfamiliar with 

“T. excelsa” in Jamaica, for he wrote in 1938 that 

the taxon was 

known to me as a living plant only in cultilation in Jamaica, 

Cuba, Trinidad, Ciudad Bolivar on the Orinoco, and British 

Guiana. It is conspicuous in its ample bright green or 

)ellowish-green leakes lighter coloied underneath, full broad 

segments, and white or nearly white soft-fleshed bead-like 

large berries; petiole broad, obtuse at maigins and compressed. It is a handsome palm. I have seen it in cultivation 

under the names T. parviflota and T. poridana. 

While working on the genus in Jamaica the 

present author decided on the basis of available 

information that the taxon under consideration 

was actually conspecific with Martius’ Thrinax 

mzilfiflora. It was clear then, as now, that the text 

and plates published in support of T. mziltiflol-a 

contained several taxa. Since no type specimen was 

known at the time, an attempt to sort out the recognizable taxa resulted in the designation of the only 

known species of Thrinax from Haiti (excluding 

Navassa) as T. muZfiflorn and relegating the miscellaneous described or figured taxa to other names. 

Alas a type specimen does exist, with a label in 

what appears certainly to be Martius’ own hand, in 

the Herbarium Regium llonacense, Munich. There 

is now no doubt about its being a Coccothiinax, 

but not the same as the one identified as Thiinnx 

aigentea by Martius. 

COMMON NAJfEs.-This palm has been known in 

Florida under a variety of names such as Florida 

thatch, Jamaican thatch, or just plain thatch. Small 

(1925) called the palm “silk-top thatch.” In Jamaica 

the palm may be called sea thatch or simply thatch, 

pronounced “tatch.” In Cuba the names “guano tle 

costa,” “miraguano de lana,” and “guano campeche” were reported by Le6n (1946). The species 

may also be known as “latanier-la-mer” or “guanillo” in Haiti and the Dominican Republic. X 

note on a specimen collected in 1959, by Dr. H. E. 

Moore indicates that the palm was called “chit” at 

the Downs of Progreso, Mexico, where it was 

collected. 

3. Thrinax excelsa Lodd. ex Grisebach 

Thrinax excelsa Lodd. ex Griseb., F1. Brit. IV. Ind. p. 515. 

1864.-Hook., Bot. Mag. t. 7088. 1889.-Read in Adams, 

F1. P1. Jam. pp. 75-76. 1972. [Type: Specimen from the 

plant illustrated in Bot. Mag. t. 7088 (K).] 

T. rex Britt. & Harris, Bull. Torr. Bot. Club 373352. 1910.- 

Howard, R. .4., Principes 4:133. 1960. [Type: Britton 4151. 

“Eastern slopes of John Crow Mountains at 450 to 600 

meters altitude,” Jamaica (NY).] 

Large palm, 3-11 m tall, caudex columnar 12.5- 

16.0 (-20.0) cm in diameter; leaf sheath 70-90 cm 

long, apex long linguiform, soon tearing away from 

petiole, not netlike, densely tan velvety throughout; petiole (1.2-) 1.6-2.2 m long, densely persistent white to tan velvety lepidote abaxially, 4.0- 

4.5 cm wide at sheath, 2.5-3.9 cm wide at apex; 

hastula irregularly truncate to broadly acute 1.8- 

2.5 cm long, 3.4-3.9 cm wide, abaxially often with 

a retuse prominence to 4 mm long near the middle; 

unexpanded blade portion densely white to tan 

lepidote on all surfaces. 

Leaf blade when expanded (2.0-)2.3-3.5 in in 

diameter circular in outline but with the outer 

segments not overlapping, free portion of segments 

drooping slightly; palman relatively flat 45-100 cm 

broad; segments (52-) 55-65 in number, narrowly 

obtrullate, 114-172 cm long, 4.4-7.4 cm wide, widest at the sinus, fused for 45-100 cm in the palman, 

rather uniformly throughout the blade, slightly 

longer toward the upper center, bifid at apex, 3.10 

cm deep, abaxial surface white to silvery densely 

lepidote tvitli interlocking fimbriate hyaline scales. 

Inflorescences 140-1 70 cm long, always arching 

at anthesis, primary bracts brown with rufous appressed scales, primary branches (10-)15-17 in 

number, about 27-30 cm long at anthesis, with 37- 

47 rachillae each, glabrous, pink to purple at anthesis; flowers rosy pink, fragrant (odor of rum and 

spice), pedicelled, 90-1 14 per rachilla, bracteoles 

shorter than the pedicels; stamens (6-)7-10 (-1 1) 

in number, anthers (1.2-)1.4-1.9 (-2.1) mm long, 

exceeding pistil in length, stigmatic area a simple 

slit in the apex of the style. 

Fruit 8.0-10.1 (-11.0) mm in diameter, pedicels 

0.4-3.5 mm long; rachillae LIP to 17.7 cm long, 

lolvermost 3.7-4.5 mm thick at the point of insertion on rachis; seed 5.9-6.0 in diameter, completely 

intruded from base to apex by testa. Haploid chromosome number, n= 18. 

SPECIMFNS Ex~~~II\.ED.-J.~X.I.;\TC.J. ST. THOSWS. “It’oodlands, eastern slopes of south end on John Crow Mountains,” 

“520 m alt.”: hlar. 1909, S. L. nritton 4151 (NY, lectotype: 

Thri~7a.v rex); Mar. 1909, Ti‘m. Harris 2 A’. L. Britton I0759 
NUhIBER 19 85 

(NY, UCWI, US; syntypes: Thiinau reu). Southwestern slopes 

of Winchester Peak, between IVheeleifield and Johnson 

Mountain: Feb. 1966, R. W. Read 1581 (CS); Mar. 1966, 

R. W. Read 1625 (BH, K, UCIVI); Mar. 1966, R. HI. Read 

1621 (US); July 1966, R. TV. Read 1682 (BH, IJ, K. UCIVI); 

Feb. 1967, R. TY. Read Ii92 (US); 29 Aug. 1967, R. TV. Rend 

.5 H. E. Moore 1963 (BH, US). PORTLA~D. Uncommon Hill 

abote Fruitful Vale: Apr. 1934. G. R. Proctor 8557 (IJ). 

Eastern slopes of John Crow Mountains aboie Ecclesdown: 

Aug. 1955, G. R. Proctor lOf83 (IJ); hlar. 1961, C. D. Adanis 

9387 (UCIVI); Apr. 1963, R. TV. Read 3 G. R. Proctor 1145 

(FTG). 

Ct LTIV4TION: Kew Gardens, May 1889 (K, holot.ipe: specimen fiom plant illustrated in Dot. Mag. pl. 7088). 

DIscussIox.-The specific epithet excelsa first appeared, without a description, in a catalog of palms 

published in 1845 by Conrad Loddiges & Sons, 

nurserymen. This very old firm, at Hackney near 

London, introduced and gave names to a number 

of palms up to that time. Many ol the names that 

appeared in their earlier catalogs had been taken 

up by several botanists before 1845; however, as 

far as can be determined the palms were all juvenile plants, and it was seldom possible to identify 

the names with living plants. The Loddiges catalog 

attributed T. excelsa to Cayenne. 

August H. Grisebach (1864) published the name 

Thrinax excelsa Lodd. with a description based on 

a plant grown at Kew and notes supplied by Dr. 

Joseph Hooker. Presumably the plant at Kew was 

already labeled with the Loddiges name. Thrinax 

excelsa was described by Grisebach as being 7 feet 

7 inches tall and had a trunk 8 inches thick at the 

FIGURE 53.--Thrinax excelsa: A, in its natural habitat on the John Crow Mountains of eastern 

Jamaica; B, an alerage-size leaf held by IYinston Barrett, an assistant to George Pioctor of the 

Institute of Jamaica. 
86 SMITHSONIAN CONTRIBUTIONS TO BOTANY 

time it flotvered at Kew. The Kew Report for 1882 

recorded that the plant of T. excelsa had grown to 

rusty-tomentose; berry globose, 3”’ diam.-Hab. Jamaica!, 

Hart. Kew. - 20 feet tall, an increase of 12 feet 5 inches in about 

18 years. Grisebach (p. 515) further described the 

palm as having 

Hooker (1889: pl. 7088) depicted Thl-inax excelsa as a plant with a broad circular leaf, white on 

the undersurface and havinc a Dink inflorescence. “I 

leaves pale-green above, hoary-glaucous beneath by minute, A betlveen plants growing in 

appressed down, divisions united to about one-third: “ligule 

bluntly deltoid:” sheath densely coated with buff-coloured 

cotton. . . . leaves 4’-5’ long, about 50-lid: divisions about 

2‘ long, ~!-1f, broad; “1igule 15”) long;” spadix branches 

spreading-recurved, its axis 1’ long, naked below; spathe 

John Crow Mountains in eastern Jamaica, with 

Grisebach’s description and pl. 7088, leaves no 

doubt that they are true T. exceZsa. Unfortunately 

the Color Of the inflorescence was not mentioned by 

FIGURE 54.-Ripe fruit and flowers post anthesis of Thrinax excelsa. Notice the silvery undersurface of the leaf blade, lower left. 
SUhlBER 19 87 

Grisebach and little notice was taken of the color 

illustration in Botanical Magazine. 

It is not known how the nurserymen in the United 

States first came to apply the name T. excelsa erroneously to a form of T. radiata being cultivated 

in Florida, but the name has been common among 

the nursery trade for many years, up to the present. 

IYhen discussing his newly described T. poridana, 

Sargent (1899) stated that, “This is the Thrinax 

excelsa of Florida nurserymen but not of Grisebach 

in Jamaica, . . . the number of stamens is said to be 

nine although this fact does not appear in the 

recent description of the species in the Botanical 

Mngazzne (115:pl. 7088).” 

In 1907, Beccari apparently became confused by 

the name T. excelsa as it appeared in the literature. 

He listed T. excelsa, of Botanical Magazine t. 7088, 

as equivalent to Coccothrinax argentea with a 

question mark, no doubt because of the white 

undersurface of the leaf. In the same list of names 

excluded from the genus he stated that the T. excelsa listed by Wendland in Kerchove de Denterghem (1878) was said to have originated in French 

Guiana, although nothing in that work has been 

found to confirm this. Then as a final gesture to 

what is without a doubt the most magnificent palm 

in the genus, he relegated “T. excelsa (Lodd.?) 

Grisebach” to synonymy with Thrinax parviflora. 

A year after the publication of Beccari’s work, 

Britton (1908) wrote in a review of the work that 

“Thrinax excelsa Lodd., as described by Grisebach, 

from Jamaica, is abundant on that island and distinct from T. fiarviflora, to which it is doubtfully 

referred by Beccari.” Britton’s criticism of Beccari’s 

work for the most part was just, but in regard to 

Thrinax, which he referred to as “probably the 

most difficult of the American genera,” he did not 

understand the complexities of the genus. Beccari 

did not “doubtfully” refer the species to T. pamflora, he only questioned the Loddiges authorship. 

Britton was correct that the species is distinct from 

T. fiarviflol-a, although present indications are that 

he was not thinking of T. parviflora Sw. but of other 

authors, and what he thought to be true T. excelsa 

of Jamaica is in fact the same T. excelsa of Florida 

nurserymen (i.e., T. mdiata). Britton and IYm. 

Harris (1910) jointly published a “Hitherto Undescribed Species of Jamaica,” Thrinax rex, discovered on the “Eastern slopes of the John Crow 

Xlountains at 450 to 600 meters altitude.” 

In the report on the Jamaican collecting trip, 

Britton wrote (1909: 102) that 

the most noteworthy tree is a magnificent fan-leaped palm 

of the genus Thrinnx, with leaves of young plants over ten 

feet in diameter, the old trees with trunks up to 60 feet 

high or perhaps even higher and nearly a foot in diameter, 

tidy the monarch of the genus, and a splendid addition to 

our knowledge of it. 

In the 1933 posthumous publication of Beccari’s 

Corypheae, the only alteration in the disposition of 

“Imperfectly known species” was the citation 

“Thrinax excelsa Lodd. ex. Grisebach F1. Brit. W. 

Ind. 515. = Thrinax Harrisiana. Becc.?’ If indeed 

this were so then the converse would be more correct, Thrinax harrisiana Becc. would be a synonym 

of T. excelsa because it is a later name. Thus it 

remained in the confusion that has persisted up to 

the present. 

Bailey (1938) accepted Thrinax rex without question, and the name T. excelsa was used for an altogether different taxon in Jamaica. The taxon to 

which Bailey applied T. excelsa is the same as that 

mentioned earlier by Sargent as the T. excelsa of 

the nursery trade and if not identical to the Florida 

taxon at least of the same species. (For a discussion 

of Bailey’s use of T. parvipora and T. excelsa see 

the discussion of T. radiata). The specific epithet 

excelsa is still commonly misapplied to the common 

Thatch Palm in landscaping, nursery trade, and 

botanical gardens around the world. 

The palm described so enthusiastically by Britton (1909) and Britton and Harris (1910) was not 

collected again until 1951 when George R. Proctor 

of the Institute of Jamaica “rediscovered” it while 

on a journey into the mountains. It was collected 

again in 1959 when Dr. R. 4. Howard OF the Arnold 

Arboretum climbed the John Crow Mountains in 

search of living material for introduction into cultivation. He wrote of his experiences in 1960. Although he felt that ‘IT. tessellata” (T. parviflora) 

was “quite common and generally undistinguished,” 

his impression concerning T. excelsa was quite different for he wrote that, “Thrinax rex [sic], however lives up to its name and even the most 

hardened botanical travellers pay quiet homage in 

looking up to this giant of the genus” which, he 

further commented, “exists in isolated splendor in 

one of the most humanly difficult environments of 

Jamaica.” 

The latest extension of the known range of T. 
88 SI\IITHSONIAS COSTRIBUTIONS TO BOTAKY 

excelsa was discovered in July of 1973 when the 

author and Dr. Ornduff of the University of California were on a raft trip down the Rio Grande in 

Portland, Jamaica. h’umerous large and small plants 

were observed growing on the cliffs of limestone 

called “Two Rocks” overhanging a section of the 

river. The most unusual aspect of this discovery is 

that the species is found well below its normal 

elevation at about 60 m above sea level and only a 

couple miles from the mouth of the Rio Grande 

near Port Antonio. 

COMMON NAhfEs.-Thyinax excelsa grotvs in a 

region of tumbled, jagged crags of honeycomb limestone where few people manage to enter. Because 

of the inaccessibility of the region, the palm is not 

well known even among the native people and 

therefore lacks a definite common name. Upon questioning some workmen in the area only one person 

knew of a palm on the ridge, which he called 

“broad thatch.” 

4. Thrinax morrisii H. Wendland 

Thrinax morrisii H. IVendl., Gard. Chron. (ser. 3) 11:104, f. 

20, 21. 1892.-Britt. 8; Wilson, Sci. Sur. Porto Rico . . . 5: 117. 1923.-Becc., .4nnal. Roy. Bot. Gard., Calcutta 

(Martelli ed.) 13:334. 1933 [“1931”].-Bailey, Gent. Herb. 

4:143. 1938. [Type: H. A. Alford NichoIls, Nov. 1891. Blowing Point, Anguilla, West Indies (K).] 

T. microcarpa Sarg., Gard. For. 9:162. 1896; Silva 10:53, t. ~511. 

1896; Bot. Gaz. 27:87. 1899; Silva 14:80. 1902.-Small, F1. 

S.E. U.S. p. 222. 1903.-Sarg., Manual Trees N. Amer. p. 

105. 1905.-Becc., 1t7ebbia 23277. 1907.-Britt., Torreya 

8:240. 1908.-Britt. & IVilson, Sci. Stir. Porto Rico. 5:117 

(pro parte). 1923.-Becc., Annal. Roy. Bot. Gard., Calcutta 

(Martelli ed.) 13:333. 1933 [“1931”].-Bailey, Gent. Herb. 

4:141. 1938. [Type: A. H. Curtiss 2679***, June 1879. No 

Name Key, Florida (NY).] 

,Simpsonin microcarpa (Sarg.) 0. F. Cook, Science (n. s.) 8.5: 

333. 1937. [Kom. illeg. Type: Thrinnx microcarfin C. S. 

Sargent.] 

T. keyensis Sarg., Rot. Gaz. 27:86. 1899; Silw 14:83. 1902.- 

Small, F1. S.E. U.S. p. 222. 1903.--Sarg., Manual Trees N. 

Amer. p. 104. 1905.-Becc., IVebbia 2:274. 1907.-Britt., 

Torreya 8:240. 1908.-Becc., .4nnal. Roy. Bot. Gard., Calcutta (Martelli ed.) 13:333. 1933 [“1931”]. [Type: C. S. 

Sargent 1886. “North shore of the largest of the Marquesas 

group of islands . . . ,” Florida (AAH).] 

T. ponceana 0. F. Cook, Bull. Torr. Bot. Club. 28:536. f. 4.5. 

19Ol.-Becc., lfebbia 2:282. 1907.-Britt., Torreya 8:240. 

1908.-Urban, Synib. Antill. 4:128. 1911.-Becc., Annal. 

Roy. Bot. Gard., Calcutta (Martelli ed.) 13:334. 1933 

[“1931”]. [Type: 0. F. Cook 1005, “dry limestone hills 

which skirt the southern coast . . , to the west of Ponce.” 

Puerto Rico-the specimen in the USNM does not have 

a number attached, hut the parts are labeled, presumably 

by 0. F. Cook, as “Thrinax ponceana CK (Type),” (US).] 

T. praeceps 0. F. Cook, Bull. Tom. Bot. Club. 28:536. 1901.- 

Becc., Webbia 2:287. 1907.-LJrban, Symb. Antill. 4: 128. 

191 1.-Becc., Annal. Roy. Bot. Gard., Calcutta (Martelli 

ed.) 13:335. 1933 [“1931”]. [Type: L. M. Underwood r3 R. F. 

Griggs 850, 13 July 1901, “precipitous mountain-side , , . between Utuado and .4recibo . . . ,” Puerto Rico (US).] 

T. bahainensis 0. F. Cook in Northrop, Mem. Torr. Bot. 

Club. 12:20. 1902.-Britt., Torreya 8:240. 1908. [Type: “Big 

Cabbage Creek, Andros Island,” Bahamas, June. KO specimen was cited hut there is material in the USNM with 

a label that reads “No. 668 Thrinax bahamensis CK type,” 

collected by Dr. & Mrs. John D. A’orthrop.] 

T. drudei Becc., Webbia 2:269. 1907; Pomona Coll. Journ. 

Econ. Bot. 3:404. 1913; Annal. Roy. Bot. Gard., Calcutta 

(Martelli ed.) 13:332. 1933 [“1931”].-Bailey, Gent. Herb. 

4: 148. 1938. [Type: “Cuba. Plantae Cubenses Wrightianae 

n. 3963 col. nome di Thrinax mtiltipora nell’ Erbario di 

Berlino ed in quello della Harvard University” (B, destroyed, GH, lectotype).] 

T. punctulata Becc., Webbia 2:280. 1907; Pomona Coll. Journ. 

Econ. Bot. 3:405. 1913; Annal. Roy. Bot. Gard., Calcutta 

(Martelli ed.) 13:334. 1933 [“1931”].-Bailey, Gent. Herb. 

4:146. 1938. [Type, Van Hermann no. 4245, 10 December 

1904. Prov. Pinar del Rio, Monte Guanajay, Cuba (identified as Thrinav mtrkiflora) (B, destroyed, NY lectotype).] 

T. ekinanii Burret, Sv. Vet. akad. Handl. ser. 3, 6(7):27. 

1929.-Bailey, Gent. Herb. 4:147. 1938. [Type: E. L. Ekman 

H. 10839, 23 Oct. 1928. Navassa Island, near the lighthouse, 

Haiti (identified on sheet as “Thrinnx ruendlnndiann Becc. 

var glnuca Ekm. et Burret”) (S).] 

Small to medium palm, 1-10.5 in tall; caudex 

columnar, slightly tapering upward, ashy gray, 

smooth, but leaf and inflorescence scars prominent, 

becoming rimose with age, (5-)8-35 cm in diameter at the base; leaf sheath 28-60 cm long, at first 

long linguiform, soon breaking apart, and separating from the petiole apically, becoming somewhat 

netlike, densely tan to white velutinous at first, 

soon becoming glabrescent; petiole 27-84 cm long, 

at first densely white lepidote abaxially, soon glabrescent, (1.0-) 1.5-2.0 (-2.1) cm wide at the sheath, 

0.7-1.6 (-2.0) cm wide apically; hastula ovateobtuse, rarely pointed, erect, thin, 0.2-0.8 cm long, 

ca 3 cm wide, densely velutinous, ciliate, often with 

dense conspicuous tufts of white or silvery indumentum when first exposed, soon becoming glabrescent; abaxial hastula rather inconspicuous, 

densely, white lepidote; unexpanded bud leaf 

(blade portion) densely appressed lepidote on all 

surfaces; expanded leaf usually glossy green adaxially; variously lepidote abaxially, with spreading, 
NUMBER 19 

interlocking, fimbriate, hyaline scales (especially 

when freshly expanded), becoming glabrescent in 

age, otherwise glaucous, blue green as a result of 

numerous minute white dots in rows associated 

with sunken stomata, the abaxial leaf color variously interpreted, depending on age and exposure; 

blade ca 75-150 or more cm in diameter, nearly 

circular in outline, the segments rarely lying in the 

same place (except in juveniles), the outer or lower 

segments often folded up and forward toward the 

apex of the blade; palman ca 12-42 cm broad; segments, rigid or lax, ca 33-58 in number, narrowly 

trullate to rhombic, pinched or not about midway; 

the longer middle segments 55-75 cm long, (2.3-) 

3.5-4.8 cm wide (at widest part), widest at point of 

fusion, apically bifid, 2-8 cm deep. 

Inflorescence 55-150 cm long, erect or arcuate, 

equaling or greatly exceeding the leaves in length; 

primary bracts silvery white to tan lepidote, often 

with apical tufts of long white scales; primary 

branches glabrous, pendant, or tufted-arcuate (when 

not fully exposed in some specimens), 9-21 in number, (8-)9-30 (-35) cm long at anthesis; ultimate 

branches 20-50 in number, 5.5-14.5 (-20) cm long, 

subtended by a narrowly triangular bract which is 

conspicuously tufted apically with white hyaline 

scales; flowers white; becoming pale yellowish or 

even pale orange with age, situated on inconspicuous disklike pedicels; bracteoles triangular; perianth 

lobes mostly acute, triangular, apiculate, rarely attenuate or abruptly rather long apiculate; stamens 

mostly 6 in number; filaments broadly connate basally into a cup or ring often equaling the perianth; 

anthers (0.8-) 1.0-1.8 (-2.0) mm long, exceeding the 

pistil in length; stigmatic area infundibuliform, 

often ciliate, the ovary often becoming orange postFIGURE %.-Thrinax morrisii: A, leaf sheath: B, leaf segments and a portion of the inflorescence 

with its bumplike pedicels. Notice the white undersurface of the folded down segment. (Photographs from the 0. F. Cook files.) 
90 SMITHSONIAX CONTRIBUTIONS TO BOTANY 

anthesis: fresh riDe fruit (3.5-)4.0-4.5 (-8.0) mm in L. H. Bailey 1009 (BH). GREES CAY. July 1903, Ti’. C. Coker 

\--,. pressed globose’ mahogany brown’ (2’3-)2*7-4’2 FLORIDA. MO%ROE COU~TY. Key Largo: May 1923, J. K. 

(-5.0) mm in diameter, mostly Only partly intruded 

by a conical cavity basally. 

Fmall, C. A. Mosier & J. B. DeTfTinkeler 10950 (US); Jan. 

1925 L. H. L- E. 2. Bailey 6162 (BH); Aug. 1929, J. K. Small 

SPECIMENS EXAMINED OR CITED.-LESSER ANTILLES. Barbuda. Near river landing: May 1937, H. E. Box 668 (BH, 

US). Southwestern part of island: South of the lagoon, sea 

level, Apr. 1956, A. C. Smith 10459 (BH, US). Near sand 

dunes: Jan. 1947, L. R. Hutson 2 (BH). ANGUILLA. Blowing 

Point: Dec. 1890, D. Morris (K. not seen, syntype of T. morrisiij; Nov. 1891, H. A. A. Sicholls (K, not seen, lectotype 

of T. morrisii); Jan. 1950, I. Vela 3749 (US). Long Bay Hill: 

June 1974, R. TY. Read 74-213 (US). 

PUERTO RICO .4ND OFFSHORE ISL.4NDS. PIIFRTO 

RICO. Dry limestone hills west of Ponce: 0. F. Cook “1005” 

(US, holotype of T. ponceana); Nov. 1902, A. A. Hellpr 

6125 (G, US); Jan. 1949, L. H. Bailey 603 (BH). Ponce to 

Penuelas: Mar. 1906, Ar. L. Britton L J. F. Coruell I300 (US). 

Tallahoa, near Ponce: May 1932, L. H. Bailey 30 & 30s (BH). 

Near Fajardo: May 1885, P. Sintenis 1324 (US). Yanco: May 

1935, F. H. Sargemt 666 (US). Salinas de Cab0 Rojo: Feb. 

1885, P. Sintenis 100 (G). Guanica: Mar. 1915, A’. L. Britton, 

J. F. Cowell c!v S. Brown 4917 (US); Jan. 1886, P. Sintenis 

3500 (G, US). Road from Utuado to Arecibo: July 1901, 

L. M. Underwood k R. F. Griggs 850 (US, holotype of T. 

prheceps): Mar. 1914, AT. L. Britton C J. F. Cowell 2049 (US). 

South of Arecibo: May 1932, L. H. Bailey 64 (BH). Camny 

to Quebradillas: Mar. 1914, AT. L. Britton S J. F. CorL3ell 1953 

(US). Lares: June 1901, L. M. Underwood ‘3 R. F. Griggs 38 

(US); Apr. 1913, AT. L. Britton, E. G. Britton ck 14’. E. Hess 

2750 (US). Between Toa Baja and Espinoza: Apr. 1921, E. E. 

Barker s. n. (BH). West of Vega Baja: Mar. 1922, A’. L. Britton, M. ,S. Brown 6 C. E. Chardon 6811 (US). Corozal: Mar. 

1923, N. L. Britton & E. G. Britton 7829 (BH, US). Near 

Bayam6n on Mogotes: June 1968, R. W. Read 2058, 2059 

(US). Guajateca Beach: Jan. 1962, Bro. Alain 9090 (IJ). 

h5oNA ISLAND. hfar. 1955, E. I>. Little L* Af. L. Kuns 16528 

(US). VIEQUES ISLAND. Feb. 1914, J. A. Shafer 2796 (US). 

TURKS AND C.4ICOS ISL.4NDS. FIVE CAYS. Prolidenciales: July 1954, G. R. Proctor 9181 (IJ). 

BAHAMA ISL.4NDS. GREAT BAHAMA. Apr.-May 1905, 

L. J. K. Brace 3709 (US). NEW PROVIDENCE. Nov. 1937, L. H. 

Bailey 1054 (BH); Nassau: hfar. 1903, A. H. Curtiss 101 (US): 

July 1903, IV. C. Coker 539 (US). HOG ISL.AND (Paradise Island). Freshwater Pond: Feb., 257 (? syntype of T. bahawensis); July 1962, R. W. Read 840 (US). ELEUTHERA. Feb.-Mar. 

1907, E. G. Britton 6515 (US). ASDROS. Big Cabbage Creek: 

Dr. 6 Mrs. J. D. Nortlwop 668 (US, holotype of T. bahainensis). Margin of Fresh Creek Lagoon: Mar. 1966, E. Y. Dawson 

26650 (US). Key near Mastic Key: Kov. 1937, L. H. Bailey 

1046 (BH). Near Fresh Creek: J. K. Small 6 J. J. Carter 

8757 (US). Deep Creek: Aug.-Sept. 1906, L. J. K. Brace 5183 

(US). West Side, in Loggerhead Creek region: h’ov. 1937, 

- & C. A. Mosier “a” & “c” (BH). Lower Matecumbe Key: .4pr. 

1932, 0. F. Cook 6 J. T. Presley (US). Long Key: Jan. 1963, 

R. TI’. Read 797 (US). Grassy Key: Jan. 1963, R. TV. Read 

798 (US). Ram Rod Key: Apr. 1932, 0. F. Cook 6 .I. T. 

Presley (US). Saddle Bunch Key: Mar. 1898, C. I-. Pollard, 

G. A’. Collins &- E. L. Morris 23 (US). Big Pine Key: Apr. 

1932, 0. F. Cook L* J. T. Presley (US); Aug. 1935, I.. H. 

nailey 42 (BH); Ang. 1929, J. K. Small & C. A. Mosier “b” 

(BH); Feb. 1937, E. P. Killip 32025 (US); Feb. 1935, E. P. 

Killip 31436 (US); Jan.-Feb. 1940, R. F. Martin, 1328 (US): 

Mar. 1936, E. P. Killil, 31717 (BH US); June 1963, R. W. 

Read 923 (US). No Name Key: June 1879, A. H. Cttrtiss 

2679”** (NY, holotype of 7. microcarpa, US); May 1891, 

J. H. Simpson 268 (US); 1881, A. H. Curtiss So. H (NY, US); 

June 1895, A. H. Curtiss (US): July 1927, H. O’Seill (US); 

Nov. 1929, 0. F. Cook (US); Apr. 1932, 0. F. Cook 2 J. T. 

Presky (BH, 1;s). Marquesas Keys: north shore of the largest, 

1898, C. ,S. Sargent (AAH, not seen, holotype of T. keyensis); 

Hotel, Miami: Feb. 1925, L. H. L* E. 2. Bailey 6350 (BH); 

hfar. 1925, L. H. Bailey 6174 (BH). C. T. Simpson’s place, 

Little River: Feb. 1925, L. H. Bailey 6342 (BH); .4pr. 1932, 

0. F. Cook &,I. T. Presley (US); June 1928, 0. F. Cook (US). 

WD.4 Plant Introduction Station, Miami: Feb. 1952, H. E. 

Moore 6010 (RH); Sept. 1962, R. TT’. Read 782, 781, (US): 

R. I$’. Read 1437 (BH). Fairchild Tropical Garden, Coral 

Gables: June 1962, R. TV. Read 771 (US); Apr. 1965, R. TI’. 

Read I409 (BH, FTG, Voucher for chromosome nnmber); 

June 1969, DeArmand Hull H-41 (BH, Voucher for M Sc. 

Thesis). SOURCE UNKNO~VN. Florida 1913 (US). 

HAITI. NAvASS.4 ISLAND. Oct. 1928, E. L. Ekinnn H. I0839 

(S, holotype of T. ekmanii; US); June 1956, C. R. Proctor 

15468 (IJ, US): Feb. 1960 S. Kiem (BH). 

CUBA, PRO\,. CAMAGUEY. Cayo Cruz: Oct. 1909, ,I. A. Shafer 

2800 (US). Cay0 Romano: Pnnta Jncaro, Oct. 1909, J. A. 

Shafer 2602 (US). Cayo Ballenato Grande: Mar. 1909, J. A. 

Shafer 947 (US). PROV. MATASZAS. Curva de Gnerro between 

Caliso and San Miguel de 10s BaAos: Dec. 1931, Bro. Ledn 

15328 (BH). San Miguel de 10s BaAos: Mar.-Apr. 1931, J. T. 

Roig (BH). PROV. HABANA. Lomas de Capasse: June 1930, 

Bro. Ledn 14583 (BH). Loma de la Janla, Capasse: Dec. 

1929, Bro. Ledn 11723 (BH). Loma Peregrina, Capasse: May 

1928, Bro. Ledn 13336 (BH). Sikrra de .4nafe: Dec. 1936, Ri-o. 

Ledn 16667 (BH, US). Sierra de Esper6n: Sov. 1932, L. H. 

Bailey 1088 (BH). PROV. PINAR DEL RIO. Xft. Guanajay: Dec. 

1904, Baker L- Van Hermann 4245 (B, destroyed, F; XY, 

Lectotype of T. punctulata); 1859-1860, Wright 3965 (AAH; 

B, destroyed; F; GH, lectotype of T. dritdei; NY, US). Sierra 

de Esper6n (“0 Anafe,” Mt. Gnanajay of Van Herman): 

AUg. 1935, I. H. Bailey ff (BH). CULTIVATED. Royal Palm 
KUXIBER 19 91 

Dec. 1936, Bro. Ledn 16667 (BH). Sierra de Anafe: Dec. 1911, 

P. Wilson 11504 (US). Vicinity of Sumidero: July 1912, J. A. 

Shafer 13414 (US). Sierra del Sumidero: Mar. 1932, L. Howell 

for Bro. Ledn 15563 (BH). La Guira: Aug. 1912, J. A. Shafer 

I3752 (US). Hills between Rio Cayaguateje and Sierra Guane: 

Nov. 1911, J. A. Shafer 10469 (US). Santa Cruz de 10s Pinos: 

Arroyo Piedras, July 1930, Bro. Ledn I4590 (BH, US). 

Vinales: Dec. 1930, E. P. KiZlip I3596 (US); Apr. 1930, Bro. 

Ledn 14369 (US). Sierra de la Guassa: Mar. 1932, L. Howell 

for Bro. Ledn 15562 (BH). Mogote de la Baudea: Dec. 1930, 

Bro. Ledn 14721 (BH). Cayos de San Filipe: Oct. 1932, Bro. 

Ledn 15860 (BH, CS). Arroyo Mamey-Pan de Quajaib6n: 

Aug. 1934, G. Sateson for Ledn 16142 (BH). Sierra del 

.41ic6n: Mar. 1932, L. Howell for Bro. Ledn I5561 (BH). 

Sierra del Rangel: ArroJ-o Aspiro, Dec. 1930, Bro. Ledn 

14724 (BH). 

DIscussIoN.-Almost from its conception, Thrinax 

mol-l-isii has been treated as a distinct but poorly 

known species restricted to two tiny remote islands 

at the extreme northeastern margin of the Caribbean Sea. As a matter of fact it was the most thoroughly known of any Thl-inax described up to that 

time. It was the only one for which the description 

and illustrations had been drawn up from excellent 

material, including mature leaves, inflorescence, 

and mature fruit. Treated simply as a dwarf, narrowly endemic species on the islands of Anegada 

and Anguilla, the name Thrinax morrisii frequently 

appeared in the literature but never in synonymy. 

It wasn’t even associated with T. Pumilio, a name 

which means “small,” from which it was said to 

differ (Wendland, 1892: 104) “in the greater number of segments of the lamina and in the shortness 

of the lamina itself.” 

Thl-inax mon-isii was first discovered in December 1890 by D. Morris, then Assistant Director of 

Kew, near a place called Blowing Point on the 

southwestern part of the island of Anguilla. In a 

report published by Norris (June 1891:131) the 

palm (without a name) was described as “present 

in fairly large quantities, and the fan-shaped leaves 

were used for thatching native huts.” Morris explained that “the chief interest attached to this 

palm is connected with its dwarf habit. The largest 

and apparently most matured specimen did not 

measure more than about 30 to 35 inches in height.” 

He was unable to find fruit or flowers at the time, 

but “30 to 40 plants . . . were carried away . . . to 

be established at the Botanical Stations at Antigua 

and St. Lucia.” Figure 56 is an old photograph, 

possibly Antigua. It is not known if these are from 

the original Morris collection, but I suspect that 

they are, since the photograph dates from between 

1902 and 1931. 

Sargent (1896) published a new species of 

Thrinax from the Florida Keys which he called T. 

microcal-pa in allusion to the small fruits (I/s inch 

in diam.). Instead of 30-35 inches, however, as in 

T. morl-isii, this new species measured 20-30 feet 

in height. He also described (p. 162) a palm growing on the Marquesas Keys (Florida), to which he 

erroneously attributed specimens of fruits with a 

“fleshy succulent pericarp.” For this, he later (1899) 

published the name T. keyensis. Thl-iizax micl-oFIGURE 56.-Small plants of Thrinax morrisii, possibly from 

the oiigiiid collection, in the Botanic Garden, Antigua. 

(Photo b) M. XI. Joseph, Dominica, in the L. H. Bailey collection at the Bailm Hoitoiium. Cornell 19373 

~~ 

depicting a group of plants in a botanic garden, I -I 
92 S\fITHSONIAN CONTRIBUTIONS TO BOTANY 

carpa was said to differ, from this species (p. 87) 

“in its taller and more slender trunk without a 

basal enlargement, in its shorter spadix and smaller 

fruit with darker colored seeds, and in its smaller 

and thinner leaves.” But characters such as “taller,” 

“more slender,” “shorter,” “smaller,” “darker,” and 

“thinner” are not considered adequate in the present treatment. Sargent (1902:80) separated the two 

species in a key only on the basis of seed and leaf 

size. 

Thrinax praeceps and T. ponceana appeared 

simultaneously in 0. F. Cook’s synopsis in 1901. 

FIGURE 57.-Thrinax morrisii growing naturally on Big Pine 

Key, Florida. (Photograph from the 0. F. Cook collection, 

now deposited in the Department of Botany, Smithsonian 

Institution.) 

Considering the results of studies on Thrinax parviflora in Jamaica, the following observations by Cook 

(1901:537) are certainly of interest: 

Several species of Thrinax, of which T. Morrisii Wendland 

may serve as an example, have been described chiefly with 

reference to the relative size of the leaf segments and the 

extent of their separation. If the palms under observation 

near Ponce belonged as was believed, all to one species, it 

is not only true that the individual Thrinax passes all the 

stages from the narrow and grass-like almost completely 

separated segments of the very young plant to the more 

than half united leaf of the large tree, but it also appears 

to be true that under unfavorable conditions a Thrinnx may 

not be able to attain full maturity of size and form but 

may at the same time produce flowers and seeds. In the narrow chinks and crevices of the bare rocks were very small, 

stunted trees, obviously of great age, while but a few feet 

distant a deeper fissure might hold vegetable debris and 

moisture sufficient to nourish vigorous specimens several times 

the size of their less fortunate companions. The stunted trees 

retain in proportion to their size, but apparently with little 

reference to their age, the small deeply divided leaves of 

young plants and have short few branched inflorescences, 

another difference of supposed systematic importance. 

Yet examination of the Cook types and his original diagnoses reveal little more than quantitative 

differences between his two new species, and no 

reference to T. mol-risii other than that quoted 

above. Unpublished notes in the Washington files 

left by Dr. Cook (in the Department of Botany, 

Smithsonian Institution) state that T. praeceps 

“differs from T. ponceana in longer and slightly 

more slender and more tomentose leaf sheaths; 

smaller, smoother leaves with longer petioles and 

smaller, more acute ligule.” These “diagnostic” 

characters are, as has been repeatedly stated, the 

real problem in palm taxonomy. The only sure way 

of separating them remains the admonition by Cook 

in the same paper (p. 526) where he stated that 

a locality definitely indicated would often go further toward 

establishing the identity of a species than much of the 

descriptive matter prepared for this purpose. For the present 

at least, the geographical idea should be kept uppermost in 

systematic studies of the palms, since it is generally much 

easier and far more logical to extend the limits of supposed 

species, than to cope with the confusion caused by the miscellaneous reporting of species far outside their natural 

ranges. 

The test of time has shown that good diagnostic 

qualitative characters, as in many other groups of 

plants, seem to be the easiest means of distinguish- 
NUMBER 19 93 

ing taxa in the Palmae; however, this has required 

a thorough understanding of ecological tolerances 

and phenotypic plasticity within the species. 

The following year (1902) Cook described yet 

another new species, this time from the Bahamas. 

Based on specimens collected by Northrop at Big 

Cabbage Creek, Andros Island, Thrinax bahamensis was said to compare favorably with Sargent’s 

T. keyensis “in view of the short pedicels, distinctly 

lobed calyx, broad filaments and short styles.” But 

“this species is evidently much smaller in all its 

parts than Thrinax Keyensis” (p. 20). And “in 

comparison with Thrinax Ponceana . , . the leaves 

of the present species are smaller with the petioles 

less flattened and more distinctly ribbed on the 

upper side near the apex.” 

In 1907, Beccari treated ten “good” species and 

three dubious species in the genus Thrinax. I now 

treat six of the ten good species as conspecific with 

T. morrisii. Two of these, T. drudei and T. punctulata, were described as new and apparently distinguished solely by the extent of the intrusion of 

the testa into the center of the seed, for they were 

placed in two subgenera separated by this character. 

While seemingly a good distinction betweeen T. 

radiata and T. morrisii, this character appears to 

be variable in T. parviflora subspecies parviflora 

in Jamaica and requires further investigation with 

more adequate material in T. morrisii in Cuba, especially since the fruits upon which the species in 

Cuba were based are immature. I find no other 

significant differences between the type of T. diudei 

(Wright no. 3965) and the type of T. punctulata 

(van Hermann no. 4245). Beccari (1913:407) felt 

the resemblance between the two species to be great 

enough to suggest that ‘I. . . it is necessary to obtain 

better specimens with flowers of both to establish 

these species on more sure diagnostic characters.” 

Descriptions of new species of palms, based on 

single incomplete specimens, have usually proved 

to be extremely questionable at best. 

When N. L. Britton and Percy Wilson (1923) 

presented their findings, they did not accept Cook’s 

two species but treated them under the earlier 

T. microcarpa of Sargent and distinguished this 

species from T. morrisii by the (p. 116) “mature 

leaves silvery beneath” for the former and “leaves 

green on both sides, or faintly glaucescent beneath” 

for the latter. 

Thrinax ekmanii was described by Max Burret 

(1929) based on collections made by E. L. Ekman 

on the island of Navassa. A limestone island with 

steep cliffs rising high out of the sea, Navassa lies 

just off the westernmost penisula of Haiti between 

Hispaniola and Jamaica. While Thrinax morrisii 

does not occur on either of the larger islands it does 

occur naturally, as presently circumscribed including 

T. ekmanii, on this tiny island. Interestingly Navassa supports another palm, Pseudophoenix sargentii. Although no really good diagnostic characters 

are known which can be used to maintain T. ekrnanii as a distinct species the most conspicuous 

thing, characterizing both palm taxa on Navassa, 

is the extremely silvery white condition of the 

abaxial surface of the leaves. Until further extensive observations of this character in the field are 

accomplished the nature of its variability throughout the entire range of the species must be treated 

as uncertain. 

COMMON NAxxEs.-Known variously in the literature as “brittle-thatch,” in Florida; “palmita” 

or “miraguano,” in Cuba; “buffalo-top,” in the 

Bahamas or “buffalo-thatch” in the Caicos Islands: 

the name “pimetta” was noted on specimens from 

Barbuda. Various herbarium specimens collected in 

Cuba bear the names, “miraguano de sierra,” “guano 

blanco de sierra,” and “guanita de sierra.” It is 

called “broom palm” in Anguilla. 
Appendix I 

Binomials Published in the Genus Thrinax 

(Arranged in chronological order) 

T. parvipora Sw., Prodr. 57. 1788. 

T. radiata Mart. ex Desf., Cat. PI. Hort. Reg. Paris, ed. 3, 

T. argentea Lodd. ex Desf. loc. cit. nom. nud. 

T. argentea Lodd. ex J. A. & J. H. Schult., Syst. Veg. 7 (2): 

1300. 1830. = Coccothrinax argentea (Lodd. ex J. A. & 

J. H. Schult.) Sarg. ex. K. Schum. 

T. pumilio Lodd. ex J. A. & J. H. Schult. loc. cit. 1301. nom. 

incert. 

T. pumila Fulch.? ex J. -4. & J. H. Schult. loc. cit. nom. nud., 

in synon. 

T. radiasta Lodd. ex J. A. 8s J. H. Schult. loc. cit. 

T. gracilis Hort. ex J. A. & J. H. Schult. loc. cit. pro syn. 

T. elegans Hort. ex J. A. & J. H. Schult. lac. cit. pro syn. 

T. aurantia Fulch. ex J. A. & J. H. Schult. loc. cit. nom. nud. 

T. m,ultiflora Mart., Hist. Nat. Palm. 3:255. 1838. = CoccoT. aurata Hort. ex Mart. ihid p. 257. pro syn. 

T. barbadensi.p Lodd. ex Mart, loc. cit. = Coccothrinax sp.? 

[not necessarily C. barbadensis Becc.]. 

T. inaritima Lodd., Cat. Palm. 1845. nom. nud. 

T. montana Lodd. loc. cit. nom. nud. 

T. stellata Lodd. loc. cit. nom. nud. 

T. ferrziginea Lodd. loc. cit. nom. nud. 

T. excelsa Lodd. loc. cit. nom. nnd. 

T. mexicana Lodd. loc. cit. nom. nud. 

T. rupestris Lodd. loc. cit. nom. nud. 

T. ? chitco Mart., Palm. Orhig. p. 45. 1846. = Chelyocarpus 

chuco (Mart.) H. E. Moore. 

T. yurnguana 4. Rich. ex Sagra, Hist. Fis. Pol. Nat. Cuba, pt. 

2. 11:278. 1850. nom. illeg. = Coccothrinax niiragziama 

(H. B. K.) Le6n [as to type, not as to plant described, 

which = C. yuruguana Le6nI. 

T. miraguano Mart., Hist. Nat. Palm. 3:320. 1853. = Coccothrinax miraguanza (H. B. K.) Le6n. 

T. Imiragziaina (H. B. K.) T\'alp., Annal. Bot. Syst. 5:818. 

1858. 

T. exceh Lodd. ex Griseh., F1. Brit. 1%'. Ind. p. 515. 1864. 

T. martii Griseh. et H. Wendl. ex Griseh., Cat. PI. Cub. p. 

221. 1866. = T. radiamta Lodd. ex J. A. & J. H. Schult. 

T. rigida Griseh. et H. Tt'endl. ex Griseh. loc. cit. = Coccothrinax rigida (Griseb. & H. Tt'endl.) Becc. 

T. crinita Griseb. et H. TVendl. ex Sauv., Anal. Acad. Ci. 

Habana 7:563. 1871. = Coccothrinax crinita (Griseb. & 

H. Wendl.) Becc. 

31. 1829. nom. nud. 

thrinax sp. 

T. acuniinata Griseh. et H. TVendl. ex Sauv. op. cit. = CocT. grandis Hort. ex Kerchove, Les Palm. 258. 1878. nom. nud. 

T. garberi Chap., Bot. Gaz. 3: 12. 1878. = Coccothrinax argetiT. graniinifolia Hort. ex Kerchove, Illust. Hort. 31:187. 1884. 

T. arborea Hort. ex Kerchove, ibid. p. 187. nom. nud. 

T. tunicata Hort. ex Kerchove, loc. cit. nom. nud. 

T. elegantissima Hort. ex Hook., f. Kew Rept. 1882:66. 1884. 

T. inorrisii H. TVendl. ex Anonymous, Gard. Chron. ser. 3, 

T. morrisii H. TVendl., Gard. Chron. ser. 3, 11:104. 1892. 

T. microcarpa Sarg., Gard. & For. 9:162. 1896. = T. tnorrisii 

T. floridana Sarg., Bot. Gaz. 27:84 1899. = T. rndiata Lodd. 

T. keyensis Sarg. ihid. p. 86. = T. tnorrisii H. Tt'endl. 

T. praecefx 0. F. Cook, Bull. Torr. Bot. Club 28:536. 1901. 

T. poncenna 0. F. Cook, loc. cit. = T. tnorrisii H. Tt'endl. 

T. bahamensis 0. F. Cook, Mem. Torr. Bot. Club 12:20. 1902. 

T. wendlnndiana Becc., TVebbia 23265. 1907. = T. radiata 

T. drudei Becc. ihid. p. 269. = T. ttiorrisii H. Tt'endl. 

T. tessellnta Becc. op. cit. 271. = T. pnrviflora Sw. 

T. punctulata Becc. op. cit. p. 280. = T. morrisii H. Tt'endl. 

T. harrisiatin Becc. in Fedde, Repert. 6:94. 1908. = T. parviT. rex Britt. & Harris, Bull. Torr. Bot. Club 37:352. 1910. 

T. longistyla Becc. in Urh., Symb. Antill. 7:170, 1912. = CocT. ekrnnnii Burret, Kungl. Sv. Vet-Akad. Handl. ter. 3, S(7): 

T. altissima Hort. ex Bailey, Gent. Herb. 4:149. 1938. nom. 

T. niirantiaca Fulch.? ex Bailey, ibid. nom. nud. 

T. compacta Griseh. & Tt'endl. ex Bailey, ibid. nom. nud. 

T. havenensis Hort. ex Bailey, ibid. nom. nud. 

cothrinax miraguama (H. B. K.) Becc. 

tutu (Jacq.) Bailey. 

nom. incert. 

pro syn. 

10:700. 1891. nom. nud. 

H. TVendl. 

ex. J. A. & J. H. Schult. 

= T. morrisii H. TYendl. 

= T. morrisii H. Tt'endl. 

Lodd. ex J. 4. & J. H. Schult. 

flora Sw. 

= T. excelsa Lodd. ex Griseh. 

cothrinax sp. 

27. 1929. = T. ~norrisii H. TVendl. 

nud. 

94 
Appendix I1 

Nomina Incerta et Dubia 

Thrinax pumilio Lodd. ex J. A. & J. H. Schult., Linn. Syst. 

T. purnila Fulch. ? ex J. A. & J. H. Schult. loc. cit. in synon. 

T. pumilio Lodd. Cat. Palm. 1846. nom. nud. 

Porothrznav H. TVendl. ex Griseb. Cat. PI. Cub. p. 221. 1866. 

Veg. sec. 7 (2):1301. 1830. nom. incert. 

nom. nud. 

The original description of Thrinax pumilio by 

J. A. & J. H. Schultes (1830) was based on material 

from a young plant sent to the Munich Herbarium 

by Loddiges. No specimen has since been found 

there that could be identified with the description. 

It could represent almost any palmate genus since 

Loddiges included plants of both Coccothrznax and 

Thrinax under Thrinax. It is impossible to apply 

the very ample description to any known species 

or for that matter to ascribe it to any genus. A 

description drawn from a young palmate leaf with 

only 10 to 14 segments is impossible to identify 

lacking a specimen. The statement that a hastula 

is not present is disconcerting, for even very young 

Thrinax and Coccothrinax exhibit this organ. 

Moreover it would seem that a Thrinax leaf blade 

2 feet in diameter should have more than 14 segments. The additional statement (p. 1301) that 

T. pumilio “Differt a Thr. parviflol-a et argentea 

praesertim defectu prominentiae in centro frondis 

a prolongatione stipites” suggests a generic difference rather than a specific one. The mention of the 

embryo must be disregarded, since it came from 

Martius and no doubt does not apply to the taxon 

in question because it is a juvenile plant by 

definition. 

Specimens cited at the time of the publication of 

Porothrinax pumilio by Grisebach (1866:221) are 

merely associated with the name and are not to be 

considered as the type. The mention of the seed 

having “the albumin centrally perforate, the margin 

not at all ruminate” is taken from associated specimens, not from type material and thus must be 

ignored in typifying Thrinax pumilio. Porothrinax 

H. Wendl. ex Griseb. was not accompanied by a 

separate diagnosis and is therefore not validly published (4rticles 41 and 42 of the International 

Code of Botanical Nomenclature). 

Thrinax section Porothrinax ascribed to Drude 

(1887) and validated by C. S. Sargent (1896) is a 

new name based on Thrinax microcarpa and should 

not be confused with the earlier invalid name 

published by Grisebach. 

95 
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