Fossil Algae From 

Eniwetok, Funafuti 

and Kita-Daito-Jima

GEOLOGICAL SURVEY PROFESSIONAL PAPER 260-Z
Fossil Algae From 

Eniwetok, Funafuti 

and Kita-Daito-Jima

By J. HARLAN JOHNSON

BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

GEOLOGICAL SURVEY PROFESSIONAL PAPER 260-Z

A description of 90 species, including 4 new ones, 

belonging to 16 genera, and a discussion of the value 

of algae as paleoecological indicators and rock 

builders

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1961
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEW ART L. UDALL, Secretary

GEOLOGICAL SURVEY 

Thomas B. Nolan, Director

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

Washington 25, D.C.
CONTENTS

Abstract-_ _________________________________________

Introduction _______________________________________

Source of material ______________________________

Eniwetok Atoll, Marshall Islands-____________

Funafuti Atoll, Ellice Islands_________________

Kita-Daito-Jima, Philippine Sea______________

Procedure- _____________________________________

Acknowledgments. ______________________________

Classification, ______________________________________

Keys to the tribes and genera of the crustose coralline 

algae_ _______________________________________

Keys to the genera of the articulated coralline algae__

Distribution and abundance-___-_-_--__-___-_---_-__-

Crustose coralline algae__________________________

Articulate coralline algae-_-____--____-__________

Green algae.___________________________________

Algae on existing reefs___---_-_-_-_---______-__-_

Algae in drill holes._____________________________

Algae as limestone builders_---_----_-_----___--------

Algae as indicators of age_________--________.-__-_-__

Algae as ecological indicators.________________________

Systematic descriptions._____________________________

Rhodophyta (red algae) _________________________

Family Corallinaceae (coralline algae) _________

Subfamily Melobesioideae (crustose 

corallines) ____________________________

Genus Archaeolithothamnium Rothpletz, 1891__ _ ____________________

Division 1—Simple crusts_-___- 

Division 2—Crusts with protuberances or short stubby branches. 

Division 3—Strongly branching 

forms _______________________

Genus Lithothamnium Phillippi, 1837__ 

Division 1—Simple crusts________

Division 2—Crusts with warty 

protuberances or short stubby 

branches..___________________

Division 3—Strongly branching 

forms ________________________

Genus Mesophyllum Lemoine, 1928. __

Division 1—Simple crusts___---__

Division 2—Crusts with short

stubby branches-_____________

Division 3—Strongly branching 

forms.______________________

Page 

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Systematic descriptions—Continued 

Rhodophyta—Continued

Family Corallinaceae—Continued

Subfamily Melobesioideae—Continued

Genus Lithophyllum Philippi, 1837__._ 

Division 1—Simple crusts. ______

Division 2—Crusts with warty 

protuberances. _______________

Division 3—Strongly branching 

forms.______________________

Genus Goniolithon Foslie, 1900_______

Genus Porolithon Foslie, 1900-_______

Division 1—Crusts. _ ____________

Division 2—Large thick masses. _

Division 3—Strongly branching

forms _______________________

Genus Paraporolithon Johnson, 1957__ 

Genus Lithoporella Foslie, 1909_______

Genus Dermatolithon Foslie, 1899-___- 

Subfamily Corallinoideae (articulate corallines) -___---_-___---_-_-___---__-_--_ 

Genus Jania Lamouroux, 1812_______

Genus Amphiroa Lamouroux, 1812____

Genus Corallina Linnaeus, 1758______

Chlorophy ta (green algae) _______________________

Family Dasycladaceae_______________________

Genus Dactylopora Lamarck, 1816____

Genus Acicularia d'Archiac, 1843_____

Occurrences of Dasycladaceae in cuttings from E-l, Eniwetok_________

Family Codiaecae.________________________>__

Genus Halimeda Lamouroux, 1812____

Occurrences of Halimeda in cuttings 

from E-l, Eniwetok. _____________

Genus Microcodium Gllick, 1912__.___

Geographic distribution and stratigraphic occurrences of

algae_ _________________-_-____---_-_-___---_--_-_

Occurrences of algae in F-l and E-l______________

Distribution of algae in boring K-l, Engebi__ _____

Distribution of algae in Funafuti boring___._-___._ 

Occurrences of algae in Funafuti boring.__________

Occurrences of algae in Kita-Daito-Jima boring... __ 

Selected bibliography-___________-__--_---____--____.

Index _____________________________________________

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ILLUSTRATIONS

[Plates follow Index]

PLATE 275. Porolithon, Go'niolithon, and Lithophyllum.

276. Lithoporella.

277. Corallina, Amphiroa, Dermatolithon, and Lithoporella.

278. Amphiroa, Jania, and.Dactylopora.

279. Halimeda, Dactylopora, and Acicularia.

280. Halimeda.

PLATE 267. Archaeolithothamnium.

268. Archaeolithothamnium.

269. Archaeolithothamnium and Lithothamnium.

270. Lithothamnium and Mesophyllum.

271. Mesophyllum.

272. Lithophyllum and Mesophyllum.

273. Lithophyllum.

274. Lithophyllum.

Page 

FIGURE 288. Sites of deep holes drilled on coral islands__________________--__-_-----_----------_---__-----_-------- 908

289. Location of drill holes on Eniwetok Atoll-________________._________-___-_________-_--_____---------_ 909

in

BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA

By J. HARLAN JOHNSON

ABSTRACT

Ninety species belonging to sixteen genera of calcareous algae 

are described and discussed. Four of the species are new. 

Most of the algae were obtained from holes drilled on Eniwetok, 

Funafuti, and Kita-Daito-Jima; a few from outcrop samples. 

The several habitats occupied by algae on the existing reefs are 

briefly described. Algae are shown to have value as paleoecological indicators. They have contributed notably as rock 

builders.

The rocks containing the algae have been dated as: Recent 

and Pleistocene (?), Miocene, and Eocene. The algal floras 

from these units are quite distinct. Many of the species observed growing on the existing reefs occur in the Pleistocene ( ?) limestones along with some additional forms. With the 

exception of the highly variable form designated as Litlioporeila, melobesioides (Foslie) Foslie, the Recent-Pleistocene(?), 

Miocene, and Eocene floras have no species in common.

Charts show the known geographic and geologic distribution 

of species. Details of the stratigraphic distribution of the algae 

in the drill holes are appended at the end of the report.

INTRODUCTION

Since the end of World War II, geological studies of 

many of the Pacific Islands have been made by the U.S. 

Geological Survey. In connection with this work, the 

author visited a number of the islands and collected 

both living and fossil algae. He has also studied the 

large collections of algae made by the parties engaged 

in mapping the islands and has studied material from 

all the deep holes that have been drilled into Pacific 

island reefs.

Descriptions of the living and fossil algae from 

Bikini Atoll have been published by Taylor (1950) and 

Johnson (1954). Descriptions of fossil algae from 

Saipan have been published by Johnson (1957).

The present paper presents information obtained 

from studies of samples from deep holes drilled on 

Eniwetok, Funafuti, and Kita-Daito-Jima and some 

comparisons with samples from Bikini. Drill holes 

on these four islands are the only ones that have penetrated deeply enough to give significant information as 

to the foundations of the atolls and their geologic history. Samples from all holes contain calcareous algae, 

and at certain levels such algae are extremely abundant. The four drilling localities are widely distributed geographically, and are separated by a considerable range of latitude (fig. 288). All but one of the 

holes penetrate rocks older than Pleistocene. The 

Eniwetok holes pass through 1,500 feet of Eocene rock.

The present study indicates that algae have contributed 

notably to reef construction.

Insofar as possible, the data on the algae from the 

various islands has been synthesized, and the species 

descriptions have been arranged systematically.

SOUECE OF MATERIAL

This report is based on the limestone cores and 

cuttings obtained from the drill holes on Eniwetok, 

Funafuti, and Kita-Daito-Jima.

ENIWETOK ATOLL, MARSHALL ISLANDS

Drilling on Eniwetok Atoll began in 1951 when 

several holes were drilled on the island of Engebi. One 

of these (K-1B) was carried to a depth of 1,285 feet. 

The following year two deep holes were drilled, 

each of which went to the underlying volcanic 

rock basement. The first, F-l on Elugelab. struck the 

basement rock at a depth of 4,610 feet. The second, E-l 

on Parry Island, reached a total depth of 4,222 feet, 

having penetrated 68 feet of basalt (fig. 289). Drill 

holes F—1 and E-l are the deepest yet made in a coral 

reef, and are the only ones that have penetrated to the 

basement material. The holes passed through a relatively thin Quaternary section before entering a thick 

Tertiary section of shallow-water limestones.

Many of the beds penetrated by the drill were very 

fossiliferous. The most abundant fossils are Foraminifera, corals, mollusks, and algae. A detailed discussion of the stratigraphy and descriptions of the other 

groups of fossils are contained in other chapters of 

Professional Paper 260.

FUNAFUTI ATOLL, EXJLICE ISLANDS

Drilling on Funafuti was done between 1896 and 

1898. The final report on the project was published as an illustrated memoir by the Royal Society 

of London in 1904 and is recognized as a classic in 

geology. Members of the Royal Society who made the 

study discussed the petrography and alteration of the 

rocks, and described in detail most of the organisms 

found in cores and cuttings. One group not studied 

or described was the calcareous algae. They recognized the presence of these organisms, but no specialist 

was available for detailed study so they were lumped 

under the general term, Lithothamnion.

907
908 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

iNORTH

MERltiA

OKINAWA KITA-DAITO-JIMA

ENIWETOK. ..BIKINI

HAWAIIAN •% 

ISLANDS >>

MARSHALL IS

.FUNAFUTI

FIGURE 288.—Sites of deep drill holes—Enlwetok, Funafuti, and Kita-Daito-Jima (position of Bikini also shown; algae described in Professional

Paper 260-M).

After the deep drilling on Bikini had been completed, the authorities of the British Museum loaned 

the Funafuti cores to the writer for comparative 

studies, and he welcomed the opportunity to examine 

the algae.

The main boring at Funafuti (drilled in 1897-98) 

penetrated to a depth of 1,114 feet. Throughout its 

length the hole was in carbonate rocks: limestone, 

dolomitic limestone, and dolomite. No Tertiary sediments were reached. Considering the date at which 

the drilling was done and the type of equipment then 

available, the expedition made a remarkable recovery 

of cores. Most of the section was in hard rock, although some of the youngest beds were friable and incoherent "sands." In the deeper portions of the boring, the limestone was found to be recrystallized and 

highly dolomitized. Unfortunately, the alteration destroyed detailed structures of many fossils.

The abundance of algae found in the cores surprised 

all the geologists who took part in the investigation. 

Statements in the report regarding the importance of 

algae have been quoted in many later publications and 

have stimulated considerable work on calcareous algae.

KITA-DAITO-JIMA, PHILIPPINE SEA

A drilling project on Kita-Daito-Jima was sponsored by Professor H. Yabe of Tdhoku University. 

The work began in March 1934 and continued for about 

6 weeks, when a depth of 209.29 meters (687 feet) was

reached. The project was resumed in January 1936 

and the drilling continued to a total depth of 431.67 

meters (1,416 feet). The work ended May 24, 1936. 

The section drilled first was mainly hard limestone, 

and core recovery was very good. In the second operation, the hole penetrated poorly consolidated material. 

The cores and cuttings were taken to Tohoku University at Sendai, Japan, where they were studied. Reports 011 the petrology of the limestones have been 

published by Y. Ota in 1938, and S. Hanzawa described 

the Foraminifera in 1941. In these reports, repeated 

mention is made of the calcareous algae as important 

constituents of the calcareous sediments, but no species 

were described.

The authorities at Tohoku University, through Professor Shoshiro Hanzawa, generously donated half of 

the entire core to the U.S. Geological Survey. This 

core is now on permanent deposit at the U.S. National 

Museum. The University authorities also loaned their 

thin sections. Numerous additional sections were prepared from parts of the core; the algae found in the 

sections are described in this report.

PROCEDURE

Genera of crustose coralline algae are differentiated 

on the basis of the character and structure of the hypothallus and perithallus and in the structure and arrangement of the sporangia and conceptacles. Species
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA

162°00' 162°10f 162-20' 162°30'

909

a

NSERTS-APPROXIMATE

ENIWETOK ATOLL

PARRY ISLAND

••-i HAWAIIAN IS

ENIWETOK

^r *xX180° 140°

INDEX MAP

162°00' 162°10' 162°20'

FIGURE 289.—Location of drill holes on Eniwetok Atoll.

are differentiated on dimensions of cells and conceptacles.

Numerous thin sections were prepared from various 

cores and from pieces of calcareous algae picked from 

drill cuttings. Each of the Eniwetok cores bears a 

letter designating the hole, followed by three numbers. The first number is that assigned to the hole,

the second refers to the number of the core run, and 

the third the number of the core piece, counted from 

the top of the core. In the laboratory innumerable cell 

measurements were made and the thickness of the 

crusts, hypothallus, perithallus, and coiiceptacles measured. Many of the data obtained are summarized in 

tables.
910 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

ACKNOWLEDGMENTS

Thanks are due the authorities of the British Museum 

of Natural History for the arrangements which permitted a restudy of the Funafuti core and the original 

slides made from it. Miss L. M. Newton of that institution prepared a list of the Recent calcareous algae 

from Funafuti determined by M. H. Foslie, which are 

now in the collections of the British Museum.

Dr. Earling Siversten, Director, and Dr. Olav 

Gjaerevoll, Curator of Botany, at the Royal Norwegian 

Natural History Society's Museum at Trondheim, 

Norway greatly assisted the writer during a visit to the 

Museum in 1950. The Funafuti collections studied by 

M. H. Foslie, including a number of type specimens, 

were made available for examination and photography 

and small fragments were furnished for thin sectioning. 

Most of the photographic plates from which the illustrations for the Foslie and Prinz Memoir (1929) were 

prepared were also located.

In addition to arranging for loan of Kita-DaitoJima material, Dr. Shoshiro Hanzawa of the Institute 

of Geology and Paleontology of Tohoku University, 

Sendai, Japan, personally assisted the writer most 

generously during several visits to Japan.

To Wataru Ishijima, Professor of Geology, Rikkyo 

(St. Paul's) University, Tokyo, Japan, and the foremost student of fossil coralline algae in Japan, the author is deeply grateful for many courtesies and kindnesses. His recent publication "Cenozoic Coralline 

Algae from the Western Pacific" (1954) has been frequently consulted.

CLASSIFICATION

Algae are classified into broad general divisions or 

phyla on the basis of the structure of the plants, and 

the chemical character of their normal pigments. The 

several phyla having fossil representatives are shown 

in the following table. All the rock-building algae 

described in the present report belong to 1 of 2 of the 

major divisions, the Rhodophyta (red algae) or the 

Chlorophyta (green algae). The classification of 

genera used is given in the table on classification. 

Generic identification keys are given later.

The important rock-building red algae belong to the 

family Corallinaceae, or coralline algae. These differ 

from the other calcareous algae in that the calcium carbonate is secreted within and between the cell walls as 

well as (in most specimens) being deposited around the 

plant tissues. For this reason, they make good fossils 

as they show recognizable and specifically identifiable 

microstructure such as the shape and arrangement of 

the cells.

Classification of fossil algae

Phylum

Rhodophyta (Red

Phaeophyta (Brown

algae). 

Chlorophyta (Green

algap).

Cyanophyta (Bluegreen algae).

Family

Corallinace ae _ 

Solenoporaceae.

[Laminariales and

others(?)] 

D asycladaceae

Codiaceae.

Charophyta.

Porostromata. 

Sponglostromata.

Characteristic structures

Rows of closely packed cells, rectangular in section. Spore cases or 

conceptacles.

Rows of closely packed cells with 

polygonal cross section. Cross partitions present though frequently 

very thin.

Corded strands of parallel threads. 

Fronded types.

A central stalk, preserved as a tube or 

bulb, surrounded by tufts of leaves 

or leaf bases, preserved as knobs or 

brushlike protuberances.

Small tubes loosely arranged so as to 

form segmented stems. Tubes 

round in cross section and branching.

Highly developed small bushy 

plants. Fossils usually consist of 

calcified heavily ribbed spherical 

oogonia and the whorled branches 

which bear them.

Small tubes loosely arranged; do not 

compress each other. No cross 

partitions visible.

Cellular structure seldom preserved. 

The CaCOs is deposited as crusts 

on the outside of the colony or cell, 

or between the tissues, not in the 

cell wall. Classified on the basis of 

growth habit and form of the 

colony.

The calcareous green algae show varied degrees of 

calcification. Among the Dasycladaceae, the lime is 

deposited around the tissue forming molds of the plants 

and plant segments. The calcareous deposit may be 

sufficiently thick to envelope the entire plant, or it 

may be so thin as merely to coat the main stem and 

the primary branches. In Halimeda, on the other 

hand, the tissue itself is calcified, the process starting 

at the outer surface and working inward. In some 

cases the entire tissue is calcified; in others, only the 

outer part.

The red coralline algae is a difficult group to classify; several different classifications have been formulated for it. The features commonly used are: (a) 

Growth form; (b) arrangement of cells and differentiation of tissue; (c) features of the conceptacles, such 

as their shape, size, and position of the distribution of 

sporangia within them and the number of roof pores; 

(d) amount of calcification; (e) similarities of strucClassification used in present report

Rhodophyta

(Red algae).

Chlorophyta

(Green algae).

Family

Corallinaceae ___

Dasycladaceae

Codiaceae _ _ -

Subfamily

Melobesioideae

(Crustose

corallines).

Corallinoideae

(Articulate

corallines) .

Genus

Archaeolithothamnium

Dermatoltthon

Ooniolithon

Lithophyllum

LUhoporella

Lithothamnium

Mesophyllum

Paraporolithon

Pmolithon

Amphiroa

Arthrocardia

Corallina

Jania

Dactylopora

Acicularia

Halimeda

Microcodium
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 911

tures; and (f) assumed relationships and evolution. 

Foslie and other students of Recent algae have tended 

to emphasize features a and c, while Lemoine and 

others who have been interested primarily in fossil 

algae have emphasized b, c, and d. In recent years, 

several students have emphasized features e and f.

The paleobotanist who works with algae is handicapped because commonly he has only fragments of 

the plants, pieces of the branches, in most cases broken 

from the basal crust, or small parts of the crust. Many 

of the fragments are sterile. When remains of the 

conceptacles are present, the chamber may be compressed, filled with foreign material, or covered with 

scar tissue that gives little indication of the roof structure. Rarely do the conceptacles show traces of the 

sporangia or indications of their distribution.

Some workers have considered the amount of calcification as an important feature in classification but the 

writer discounts this, as a number of external factors, 

including the age of the plant, appear to be involved; 

old plants are commonly much more calcified than 

young ones.

The use of similarities of structures in classification 

is hazardous. In many instances such similarities do 

mean close relationship but they may be developed in 

unrelated stocks as a result of parallel evolution or as 

a response to living in a similar, rather specialized, 

environment.

Lenjoine (1911) has shown that it is possible to divide the Recent genera of the crustose corallines into 

two groups based on the arrangement of the cells. In 

the first group, represented today by Lithothamniwn, 

the basic structure is a row of cells usually growing 

nearly vertically. In the second group, the basic structure is a layer of cells spreading horizontally or roughly 

parallel to the outer surface of the plant. Other features commonly fit in with these two subdivisions. For 

example, almost all of the plants showing the first type 

of tissue structure have conceptacles whose roof is 

pierced by multiple pores, while practically all of those 

having the second type of tissue structure have conceptacles pierced by a single pore.

The group that causes the most trouble, both in preparing the classification and in identifying the individual fossils, consists of extremely thin forms having 

a crustose thallus that is formed of one or, at most, 

of only a few layers of cells. It is not surprising that 

in this group there has been confusion in the definition 

of genera. In many cases, it is impossible to refer a 

specimen to a given genus unless conceptacles are present. It is not known if the thin crustose forms represent an original simple structural type or are highly

simplified descendants of ancestors that originally had 

a much more complex thallus.

The author agrees with Lemoine that the character 

of the basal hypothallus should be considered as a very 

important feature in classification. He is not so sure 

as to the value in classification of the medullary hypothallus of branching forms, as there seems to be a tendency among all highly branching forms to develop a 

medullary hypothallus. This is true among Lithothamnhnn., Lithophyllum^ and Archaeolithothamnium. 

The medullary hypothallus is also a prominent structure among the articulated coralline algae, all of which 

are branching- forms.

KEYS TO THE TRIBES AND GENERA OF THE 

CRUSTOSE CORALLINE ALGAE

[Genera marked with asterisk (*) were found in Eniwetok drill holes]

I. Sporangia collected into conceptacles__ _______ ^__.-_, Ill

Sporangia not collected into coiiceptacles______ _______ II

II. Tissue many layered with hypothallus and perithallus— 

Archaeolithothamnium*

III. Conceptacles perforated by a few or many pores—Tribe 

Lithothamnieae_ __--__-----________..___________ IV

Conceptacles perforated by a single pore—Tribe Lithophylleae__-_---____- ____________________________ V

IV. Roof of sporangial conceptacles perforated by few to many 

pores—Tribe Lithothamnieae_ __-__-_-_______ 1

1. Thallus self-sustaining, not parasitic.______________ 2

2. Ilypothallus a single layer of cells, at least in part; 

thallus epiphytic. Hypothallic cells in section, 

square or somewhat horizontally elongated— 

Melobesia 

2. Hypothallus of many layers of cells;

3. Hypothallus of curved rows of cells__________ 3A

3. Hypothallus coaxial (arched rows or layers of cells)—

Mesophyllum* 

3A. Sporangial conceptacles superficial or subimmersed—Lithothamnium* 

3 A. Sporangial conceptacles deeply immersed—Clathromorphum 

V. Roof of sporangial conceptacles perforated by a single

pore—Tribe Lithophylleae 

1. Megacells present___--_--______________________ 2A

1. Megacells absent------------__-_-----___----___ 2B

2A. Hypothallus consists of a single layer of cells____ 3

3. Hypothallic cells vertically and obliquely elongated—Hydrolithon

3. Hypothallic cells square or nearly so—Fosliella, 

2A. Hypothallus of several to many layers of cells___ 3 

3. Megacells in lenses or horizontal clusters—Porolithon *

3. Megacells singly or in vertical rows—Goniolithon * 

3. Megacells in both horizontal and vertical clusters—

Paraporolithon 

2B. Hypothallus composed of cubic cells___________^ 3

3. Thallus of several layers of cells—Heteroderma

3. Thallus of many layers of cells, not epiphytic—

LithophyUum *

2B. Hypothallus of one or two layers of obliquely elongated cells- _______________________________ 3
912 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

V. Roof of sporangial conceptacles perforated by a single

pore—Tribe Lithophylleae—Continued 

2B. Hypothallus of one or two layers of obliquely elongated cells—Continued

3. Thallus characteristically epiphytic or epizoic 

commonly expanding locally to two or more layers 

with cells nearly equidimensional—Dermatolithon * 

3. Thallus prostrate, epiphytic, or epizoic often superimposed—single layered except immediately 

around conceptacles, cells vertically elongated— 

Lithoporella *

KEYS TO THE GENERA OF THE ARTICULATE 

CORALLINE ALGAE

[Genera marked with asterisk (*) were found in Eniwetok drill holes]

I. Segments consist of several or many tiers of cells__ II

b. Segments consist of a single tier of long cells—

Lithotrix 

II. a. Each tier composed of regular cells with straight

walls_ — _________________________________ III

b. Tiers composed of irregular, sinuous and interlacing cells. (Conceptacles lateral. Nodes 

formed of a single tier of cells)—Calliarthron 

Til. a. Boundaries between tiers of cells essentially

regular.. ___________________________________ IV

b. Boundaries between tiers of cells irregular, commonly more or less stepped. Cells commonly 

wedge shaped. Segments small, slender, cylindrical. Conceptacles terminal—Jania*

IV. a. Tiers of cells of principally the same length_____ V 

b. Commonly there are tiers of long and short cells 

variously alternating. Segments show considerable variation in size and some variation 

in shape. Commonly they are cylindrical or 

flattened cylindrical. Nodes rather inconspicuous, of one or several tiers of cells. Conceptacles lateral—Amphiroa*

V. a. Tiers of cells gently but evenly arched. ________ VI

b. Tiers of cells flattened in central area, curving 

downward sometimes abruptly, toward the 

margins. Nodes of a single tier of cells. 

Branching regular, pinnate. Conceptacles are 

terminal—Arthrocardia*

VI. a. Segments not of same shape in different areas of

the same plant.___________________________ VII

b. Segments cylindrical or flattened cylindrical. 

In section, commonly wider at top than at 

base. Notes conspicuous with a single tier of 

very long cells. Branching commonly in a plane, 

pinnate. Conceptacles terminal—Corallina* 

VII. Segments commonly clavate, but may be oval, 

rounded, flattened or polygonal in section.

1. Biforcating branching. Conceptacles on margins of upper lobes of segments—Cheilosporum

2. Segments commonly cylindrical or nearly so 

near base of the frond becoming trapezoidal 

above. Branching pinnate. Conceptacles 

at the end of the lateral branches—Joculator

3. Segments cylindrical or compressed cylindrical 

below, becoming flattened above with oval 

cross section. Branching dichotomous or 

alternating. Nodes consist of a single zone 

of cells. Conceptacles lateral—Bossea

DISTRIBUTION AND ABUNDANCE

The distribution of living calcareous algae is controlled, or at least strongly influenced, by a number of 

ecologic factors and, presumably, fossil species were 

similarly controlled. The most important factors are 

depth, salinity, temperature, intensity of light, turbidity, and, in the case of shallow-water forms, the character of the bottom. Each species adjusts itself to all 

of these factors.

The intensity of light seems to be the most important factor, with salinity ranking next. The depth 

range of a given species probably reflects the combined effects of light, salinity, agitation, and circulation. Experiments with some shallow-water forms 

have shown that they can tolerate a considerable variation in temperature and salinity for at least short 

times. Also, that they can stand abnormally high 

salinity better than a deficiency. Most of the coralline 

algae seem to require clear water, but some of the green 

algae are able to withstand appreciable amounts of 

mud or fine silt, although they too thrive best in clear 

water. The coralline algae commonly attach themselves to some hard substance, rock, coral, or fragments 

of hard organic debris, such as shells, fragments of 

coral, or other coralline algae. The green calcareous 

algae frequently spread over mud, lime mud, or even 

sandy bottoms.

•9

CRUSTOSE CORALLINE ALGAE

The crustose coralline algae (subfamily Melobesioideae) are widely distributed both geographically and 

geologically. They are found in all the existing 

oceans, from the tropics to polar waters. Certain 

genera such as ArchaeoUthothamnium, Goniolithon, 

and Porolithon occur only in the tropical and warm 

temperate seas. Lithothamnium occurs in all seas but 

has its greatest development in the cold and cool temperate waters; Lithophyllum prefers the warmer 

waters, although some cool-water species are known.

Along rocky coasts in many places calcareous algae 

are found as thin white or pink crusts coating the 

rocks or forming shelves along the foreshore; they also 

occur in abundance immediately below low-tide level. 

Most branching forms develop in the zone between lowtide level and depths of 80 to 100 feet in the areas 

studied for this report; at greater depths the prevalent 

growth forms are crusts, which become smaller and 

thinner as the depths become greater. They are rare 

at depths below 400 feet, but specimens have been 

dredged from depths of 575 feet.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 913

Each of the littoral and sublittoral zones is characterized by certain species. Along the English 

Channel, for example, of the 14 species of crustose 

corallines observed, 5 were found only in the littoral 

zone, and 3 occurred only in the sublittoral, while 6 

occurred in both zones. Species characteristic of the 

littoral zone do not occur at depth. Similarly, forms 

characteristic of deeper waters seldom occur close to 

the surface. Observations made by Taylor (1950), 

Weber van Bosse (1904), and Dawson (1944, 1952, 

1954) show a similar ecological distribution in the 

tropics.

Many Recent genera of the Melobesioidaea may be 

traced to Late Cretaceous times. A few, such as 

Porolitlion and Gfomolithon., did not become abundant 

until the Pleistocene.

ARTICULATE CORALLINE ALGAE

The articulate corallines (subfamily Corallinoideae) 

also have a fossil record dating back to Cretaceous 

times. Today, they occur in the shallow waters of 

warm and temperate seas. CoraUina and Jama are the 

only genera that occur in cool and temperate waters. 

Along the European coast, CoraUina officinalis has been 

found as far north as 71 degrees (Lemoine, 1940, pi. 

114). Amphiroa reaches as far north as the Mediterranean Sea and the Gulf of California. In tropical 

areas, Corall'ma, and Jania occur with Amphiroa. The 

other genera are relatively rare and are restricted to 

warm waters.

Around Pacific coral reefs, articulate corallines have 

been collected at depths ranging from low-tide level 

to more than 100 feet but they are most common in shallow water. Tufts and patches of them may be found 

in pools in the reef flat or on the undersides of masses 

of coral or beach rock. Locally they may be abundant 

in the lagoons close to the reefs or island beaches.

Away from the reefs they also occur along rocky 

coasts. Some species grow in abundance attached to 

the rocks at about tide level in areas of strongly agitated water. Other species grow in rock pools immediately below the level of low tide.

GREEN ALGAE

Recent Dasycladaceae live in warm marine waters. 

They attain their greatest abundance and variety in 

the tropics but extend into warm temperate seas. They 

occur as far north as the Mediterranean coasts of 

France and southern Europe; 011 the eastern side of 

the Pacific, they occur on the California coast.

They are generally found in shallow marine waters, 

although they have been observed in bays and estuaries 

where the water is slightly brackish, and in a few 

lagoons where the water has a salinity higher than 

normal. Their range is approximately from low-tide 

level to depths approaching 250 feet, but they occur 

abundantly only in depths of less than 30 feet and 

especially in 10- to 15-foot depths (Lemoine, 1940, 

p. 124).

The writer has collected them on the reef flats 

around the island of Guam where at low tide they can 

be found on the underside of rocks or masses of coral 

in shallow tidal pools where they are sheltered both 

from the violence of the waves and from strong sunlight. A few were also found on the reef flats of 

Okinawa in similar surroundings; in 1 or 2 localities, 

sizeable patches were found growing on a sand bottom 

15 to 18 feet below sea level. Taylor (1950, p. 49-50) 

described Neomeris which he found on the tops of loose 

coral fragments on the reef flats and to depths of 25 

feet. He also found a species of Acetabularia, which 

was obtained by divers at a depth of 30 feet.

Yamada (1934), in discussing the green algae of the 

Ryukyu Islands, described a number of species belonging to several genera from various places, all of which 

were found in tidal pools or at depths of a few meters.

Dasycladaceae commonly grow on sandy bottoms, on 

sandy clay bottoms, and on mud bottoms. They attach themselves to these relatively loose sediments with 

the aid of numerous fine hairlike growths. They also 

grow on loose pebbles, rock fragments, boulders, and 

on the underside of rocky masses and large corals in 

rock pools of the intertidal zone of reef flats and 

lagoons.

They range from Cambrian to Recent. Locally, 

from time to time they have been important limestone 

builders. They appear to have reached their zenith 

during the Late Triassic or Early Jurassic and to have 

been slowly declining since then. Dasycladacean limestone occurs abundantly in the Ordovician of Scandinavia, the Silurian of the Baltic region, the Permian 

of the southwestern United States, Japan, and the 

Adriatic region, and the Triassic of south-central 

Europe.

Halimeda is limited largely to the tropical and subtropical waters. It is common in the tropical Atlantic, 

tropical Pacific, and Indian Ocean, and is also found in 

the Mediterranean and in the Caribbean region. In 

the Pacific, it occurs as far south as 32° on the west 

coast of Australia and in the Atlantic, to 34° south on 

the east coast of South Africa. It extends northward
914 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

in the western Pacific through the Ryukyu Islands and 

up to the southern, coast of Japan. Specimens have 

been reported from numerous localities in Japan and 

even from Kamchatka. The latter appear to represent 

material carried north by the Japan current.

Specimens of fossil Halimeda have been reported 

from rocks as old as Late Cretaceous. They have been 

found in the Tertiary at many localities.

Species of Halimeda occur on both sandy and rocky 

bottoms and develop from areas exposed at low tides, 

down to depths more than 180 feet in the area studied 

for this report. Numerous species and forms have been 

described. They represent adaptations to a variety of 

environmental conditions. Some are found only in 

shallow water on sandy bottoms. Others grow attached 

to the rocks, particularly in crevices and holes in the 

rocks; still others seem to develop best in the depressions and holes on the reef flat. The most luxuriant 

growths have been recorded in lagoons adjacent to reefs. 

Taylor, in his report on the plants of the Bikini area 

(1950, p. 76-93) gave considerable data on the ecological occurrences of Halimeda. He described 14 species 

and 11 forms of subspecies. Of these, only one was 

collected from the outer slope of the reef where it occurred at depths of 150 to 275 feet. Three occurred 

along the marginal zone of the reef in holes or crevices 

between corals or in the reef rock. Eight were common on the reef flat, and 18 occurred in the deeper waters of the lagoons, mainly, at depths of 120 to as much 

as 180 feet.

ALGAE ON EXISTING BEEFS

Existing atolls normally consist of: (a) An outer 

seaward slope, (5) a marginal zone, (c] a broad reef 

flat, and (d) the lagoon. Each of these areas (Emery, 

Tracey, and Ladd, 1954) has a characteristic assemblage of algae.

The seaiuard slope.—Crustose coralline algae occur 

along the outer slope, abundantly at the top but in 

decreasing amounts with depth. Large colonies of 

branching forms are abundant near low-tide level and 

are common to depths of 50 or 60 feet but are seldom 

found much deeper. In general, the colonies become 

smaller and the branches shorter and more widely 

spaced with depth. Thin encrusting forms are present 

at tide level but become more abundant with depth, 

with a maximum development at around 125 to 150 

feet. At greater depths they become smaller, decrease 

in number, and have a darker color. Living specimens 

were dredged from depths as great as 1,100 feet at 

Bikini but they were small and scarce.

Locally, some articulated corallines develop on the 

upper parts of the reef slope, commonly at depths of

from 10 to 50 feet, but they have been dredged from 

depths as great as 100 feet. Halimeda has about the 

same distribution as the articulated corallines.

The marginal zone.—Normally this is the area 

where the greatest development of calcareous algae 

occurs, culminating at times with the formation of the 

so-called Lithothamnium Ridge. This is probably the 

most spectacular development of coralline algae to be 

seen anywhere. Originally named the Nullipore Ridge 

by early writers, the term "Lithothamnium Ridge" is 

today somewhat a misnomer because the genus Lithothamnium has been broken up and, in the tropics, members of the genus, as now recognized, have little to 

do with building the ridge. For example the welldeveloped ridge at Bikini is built almost entirely by a 

few species of Porolithon. The term "algal ridge" 

used by some authors would be more correct.

On the windward side of the reefs, waves beat with 

force and along the reef margin there is a development 

of rounded algal heads, usually compact colonies of 

highly branching forms, such as Porolithon gardineri. 

At normal low tide, the outer part of the reef margin 

may be exposed a foot or t\vo above low-tide level, but 

is always kept moist by spray from the surf. This 

belt, normally, is rather narrow. At exceptionally low 

tides it may appear as a strip 40 to 50 feet wide, sometimes more, but frequently less. Behind this ridge, 

in the area of less agitated waters, the reef margin 

grades into a nearly smooth algal pavement composed 

of crustose nonbranching algae such as Porolithon 

onkodes. The algal ridge may appear as a continuous 

strong outer reef margin or, if the surf is very heavy, 

it may be cut by numerous surge channels. Commonly, 

the calcareous algae are the only plants found along 

the algal ridge, but corals, rnollusks, and echinoderms 

may be present in varying numbers particularly on the 

inner more protected areas.

The reef flat.—Behind the marginal zone, the reef flat 

normally extends toward the lagoon. In many places 

corals grow luxuriantly on the seaward part of the reef 

flat. Algae may grow with them, both crusts and small 

heads of branching types of the crustose corallines, tufts 

and clumps of articulated corallines, patches or tufts 

of Halimeda, and occasionally a few Dasycladaceae. 

In addition to these, noiicalcareous algae may be common, especially various types of green algae and occasionally some brown or red algae may be present. In 

some places, where there is a wide reef flat along the 

shores of islands, wide stretches or patches of the otherwise barren inner reef flat may be covered with brown 

algae.

The lagoon.—This is another area where algae may 

be abundantly developed. In areas between islands
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 915

the reef flat slopes gently into the lagoon. Commonly 

at depths of more than 10 to 25 feet the bottom may 

be carpeted with both calcareous and noncalcareous 

algae. Among the former, Halimeda may be abundant 

even down to depths of 150 to 175 feet. In such areas 

Halimeda segments are the main constituent of the deposits on the lagoon floor. Chapman (1901, p. 163- 

164) made an analysis of the organic content of 18 

samples dredged at half-mile intervals across the Funafuti lagoon. Fifteen of these were at depths of 15i/£ 

to 26 fathoms and the percentage of Halimeda ranged 

from 75 to 99. In the final report on the Funafuti 

expeditions Halligan (1904, p. 160-164) reported on 

two holes drilled in the lagoon floor. The Halimedarich sediment that covered the bottom was found to 

continue virtually unchanged for a thickness of 70 

feet or more. In 1955, V. J. Chapman discussed Recent 

Funafuti algae.

Along the shores of islands and in the shallower 

margins of the lagoons, besides Halimeda, tufts of articulated corallines and small crustose corallines occur. 

Dasycladeceae may be found growing under other 

algae and on corals in the shallow waters and more 

rarely may develop into sizable patches at depths of 

from 10 to 35 feet, especially on areas of fine sediment.

ALGAE IN DRILL HOLES

In all the samples studied coralline algae were 

abundant in the Eecent and Pleistocene (?) deposits; 

Halimeda was also present, at some places in abundance. 

In the Miocene and Eocene deposits algae occur in 

considerable abundance but they are not uniformly 

distributed. At some levels they are common, at others 

rare or entirely absent. Data on the distribution of 

algae in the various drill holes are given in the section, ''Geographic distribution and stratigraphic occurrences of algae" at the end of this report. Many 

of the gaps represent parts of the section from which 

neither cores nor cuttings were recovered. A discussion of drilling and recovery is given by Ladd and 

others (1953) and by Ladd and Schlanger (1960).

ALGAE AS LIMESTONE BUILDERS

Studies of the samples obtained from the Funafuti 

drill hole (Royal Society of London, 1904) showed that 

calcareous algae were present from the surface to the 

bottom of the hole at 1,114 feet and that at many 

horizons they contributed notably to the bulk of the reef. 

Recent studies in the Marshall Islands and in the Mariana Islands have shown that algae play a vital role 

in building the framework of the reef (Emery, Tracey, 

and Ladd, 1954; Johnson, 1954b, 1957). The drill 

samples from Eniwetok, Funafuti, and Kita-DaitdJima indicate that during much of Cenozoic time algae 

ranked next to Foraminifera in the volume of the material contributed to the reef. Only locally and temporarily were the corals as important as the algae in 

reef construction. Among the limestones studied, the 

percentage of algae by volume ranges from a low of 

3 percent to a high of about 48 percent and averages 

about 17 percent. The crustose coralline algae and 

Halimeda are the important contributors with minor 

amounts of articulated corallines. A few Dasycladaceae 

were seen in the Eniwetok and Kita-Dait5-Jima drill 

samples, but were too rare to be of real importance 

as rock builders in these areas.

Today a number of species of Halimeda occur abundantly on and around the reefs, especially in the lagoons, and locally contribute considerably to the limestones. Some of the slides and specimens studied show 

that certain beds penetrated by the drill at Funafuti 

and Eniwetok were truly Halimeda limestones. These 

were quite common at Funafuti, occurrino; at intervals 

throughout the depth of the boring. They are not so 

abundant at Eniwetok but were especially well developed in the post-Tertiary beds.

In reef building, the coralline algae are the most 

important group. They assist in the formation of 

reefs in three ways: (a) By growing abundantly along 

the margin of the reef, particularly where the surf is 

strong, to form an algal ridge which breaks the force 

of the waves and protects the reef from erosion; (b) 

by acting as a binder to cement coral heads and fragments of other organisms into a more or less compact 

mass; and (c) by contributing to the volume of the 

reef mass. Taylor (1950, p. 28-30) gave a vivid description of the algal ridge at Bikini. Emery, Tracey, 

and Ladd (1954) and Johnson (1954 a, b) also discussed this feature and the importance of the work of 

the algae in reef construction.

ALGAE AS INDICATORS OF AGE

Studies made by Pia (1926, 1927) and by Mme. 

Lemoine (1939) in southern Europe and in the regions 

around the Mediterranean Sea showed that algae have 

considerable value as index fossils. Mme. Lemoine's 

work in Algeria revealed that the algal floras of each 

Epoch are quite distinct. Only a few Cretaceous species continue into the Eocene, whereas the Miocene 

floras are distinctly different from those of the Eocene 

and the Oligocene. Lemoine concluded that algal 

species have value in correlation as far as periods or 

epochs are concerned, but only in local areas can they 

be used for detailed stratigraphic correlation. She 

foilncl, for example, that a species which occurs in the 

lower Eocene of Spain may occur in the middle Eocene

584500 O -61 -Z
916 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

in Libya or Morocco and be found even in the upper 

Eocene in Egypt or Persia, but very rarely does it 

extend into the Oligocene. The Mediterranean region 

is the only area in which sufficient work has been done 

on fossil algae to give us a knowledge of their time 

range. Until such work has been done in many other 

areas, the value of algae in correlation will be limited. 

The current studies of the geology of the Pacific 

Islands offer an opportunity to accumulate data for this 

purpose. Algae occur abundantly associated with 

Foraminifera whose time range is accurately known; 

consequently, the algae found in the various limestones 

can be dated with some assurance.

When studies of the algae and Foraminifera. have 

been made from a larger number of islands, it will be 

possible to prepare a comprehensive chart showing the 

time range of the algal species in the Pacific region. 

A chart of this type presenting the data now available 

is given at the end of this paper. It will be noted that 

most of the species do not have a long time range.

ALGAE AS ECOLOGICAL INDICATORS

The algae can also be useful in interpreting the environment of deposition. Ecological studies in areas 

of the present seas have shown that the crustose types 

of coralline algae are found in abundance from the 

intertidal zone down to a depth of about 330 feet, and 

they occur sparingly to even greater depths. Those 

forming thin crusts or sheetlike masses seem to range 

from tide level down to the limit of light penetration, 

whereas those types that develop as masses of long 

branches seldom occur at depths greater than 30 feet. 

Articulated corallines grow from tide level to depths 

not exceeding 250 feet but do not appear to develop 

abundantly in depths greater than 75 feet. Algal distribution is affected not only by depth but by such factors as light, agitation of water, character of the bottom, the presence or absence of sediment, and the salinity of the water. The relation of these factors to 

the distribution of modern lime-secreting algae has 

been studied by a number of botanists, and the results 

were ably summarized by Lemoine in her 1940 paper 

and in a paper by Maxwell Doty on rocky intertidal 

surfaces (1957). Data on present-day distribution of 

many forms in the Marshall Islands are given by Taylor (1950) and Dawson (1957). Additional information on distribution is given under the generic descriptions in this paper.

Similar studies have been made regarding the distribution of the green algae. HaUmeda thrives best 

in relatively shallow waters, from about tide level down

to depths of about 50 or 60 feet, although specimens 

of some species have been found growing at depths of 

more than 250 feet. Luxuriant "Haltmeda meadows" 

have developed over considerable areas of lagoon bottom at Bikini and Eniwetok. The author has observed 

similar developments in the shallow lagoon northwest 

of Peliliu in the Palau Islands, and over smaller 

areas at Ulithi Atoll and around Guam.

Pia (1927) has shown that the presence of abundant 

remains of Dasycladaceae always indicates shallow water and usually a muddy or silty bottom. In the present seas they are most abundant in depths down to 30 

feet. They are rarely found at depths below 50 feet.

SYSTEMATIC DESCRIPTIONS

Phyllum RHODOPHYTA (RED ALGAE)

Class RHODOPHYCEAE

Order CRYPTONEMIALES

Family CORALLINACEAE (coralline algae)

Subfamily MELOBESIOIDEAE (crustose corallines)

Description.—Characteristically strongly calcified, 

showing a great variety of growth forms. Some are 

monostromatic, others form crusts more than a centimeter thick. Crusts may be smooth, covered by protuberances, or branched. Some species develop loose 

branches or aggregates of branches.

A key to the tribes and genera was given earlier in 

the section on "Classification."

Genus ARCHAEOLITHOTHAMNITJM Rothpletz, 1891

Description.—Hypothallus consists of rows of cells 

that start horizontally, then curve upward into perithallus. Normally in perithallus vertical (transverse) 

cell rows more prominent than horizontal (longitudinal ) layers. In some species growth zones may be distinguished. Most characteristic feature of genus found 

in the sporangia, which are not collected into conceptacles but occur in lenses or layers in tissue. They may 

be packed closely together, or may be separated from 

one another by thin segments of tissue.

Today the genus is restricted to warm marine waters, 

with a known depth range of from 1 to 130 feet. It 

appears to be most common in depths from 25 to 65 

feet. ArchaeoHthothamniwn has a geologic range 

from the Early Cretaceous to Kecent. It reached its 

greatest development during the Eocene.

For convenience in classification species are grouped 

into three divisions based 011 the growth form of the 

plant. The following table shows dimensions and distribution of species.

Nineteen forms recognized, three of these being new.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA

Measurements (in microns) ana distribution of species of Archaeolithothamnium

917

Species

Hypothallus cells

Length Width

Perithallus cells

Length Width

Sporangia

Height Diameter

Locality Depth (feet) Age

Division 1.—Simple crusts

[Commonly thin; several layers may be superimposed]

Archaeolithothamnium crustatum Johnson n. sp_._

marshallensum Johnson n. sp _~ .-_

15-23(27)

12-20 

9-19 

15-28 

9-21 

5-8 

7-10

15-23 

11-15 

7-12

9-13

12-13 

7-11 

10-15 

8-12 

10-14 

7-11

8-15 

6-9

7-8

11-19

12-15 

8-13 

14-18 

9-12 

8-14 9-11

10-15 

11-13 

7-11

9-12

10-13 

6-13 

10-13 

7-10 

7-12 

5-10

8-12 

7-11

6-8

85-115 

141 195

76-96

56-76 

62-96 

37-73

100-126 

75 

48-60

41-50

75-100 

44-63 

25-30 

32-49 

30-59 

46-70

58-69 

50 

30-36

Eniwetok F-l, 

Eniwetok E-l

Eniwetok F-l.. _ 

_.-.. do. ........ ....

— ..do. ....... -_--

— -_do. ... .........

Kita-Dait5-Jima. .

do

.... _do...__— - —

12, 000 

2, 662-2, 681 

1, 718-1, 740 

2, 675± 

1, 725-1, 995 

1, 978-2, 003 

3, 655-3, 988 

51- 513 

691- 698

4, 528-4, 553 

1, 718-1, 740 

4, 528-4, 553

Miocene.

Do. 

Do. 

Do. 

Eocene. 

Pleistocene (?) 

Pleistocene or 

Recent. 

Eocene. 

Miocene. 

Eocene.

Division 2.— Crusts with warty protuberances, mammillae, or short stubby branches

Archaeolithothamnium erythraeum (Rothpletz) 

Foslie.

10-40 

12-40

9-12 

10

11-13

14-20

13-19 

12-16 

12-14 

13-23

11-19 

8-11

8-10

8-10 

8-12 

9-14 

9-14

8-12 

8-11

75-90

95-119 

63-86 

145-165 

100-131

48-65

45-55

70-90 

30-50 

96-100 

55-90

43-45

-— do.—.—... .-

Eniwetok E-1...-- 

Eniwetok F-l_— 

Eniwetok E-l...._ 

Eniwetok F-l._ ... 

-...do.....— — -

..-.do......— ....

Eniwetok E-l.__~

748- 899

867- 874 

2, 340-2, 660 

4, 528-4, 553 

2, 802-2, 808 

3, 655-3, 665 

4, 197-4, 202 

3, 655-3, 665 

2, 730-2, 740

Pleistocene or 

Recent. 

Pleistocene. 

Miocene. 

Eocene. 

Do. 

Do. 

Do. 

Do. 

Do.

Division 3. — Strongly branching forms

16-27 11-14 11-16 

20-24

9-10 

9-12

90-120 

90-136

34-36

54-75

Eniwetok E-l—— 

.... .do.....— — ...

2, 350-2, 360 

2, 802-2, 808

Miocene. 

Eocene.

Division 1—Simple crusts

Archaeolithothamnium crustatum Johnson, n. sp. 

Plate 267, figures 1, 2

Description.—Thallus thin, crustose, frequently 

growing superimposed. Hypothallus 0.5-1.3 mm 

thick, composed of few layers of slightly curved nearly 

horizontal rows of cells 15/X-23/X (27/x) long and 

9/X-13//, wide. Perithallic tissue quite regular, with 

well-defined transverse cell rows and fairly well 

marked longitudinal layers. Cells ll/x-19/x, long and 

9/A-12/X wide. Sporangia long, ovoid, measuring 85/x115/x high and 41/X-50/X in diameter.

Remarks.—This form resembles Archaeolithothamnium intermedium. Eaineri but has larger sporangia 

and more regular perithallic tissue without alternations of layers of cells of different length. It is close 

to the Eocene species from Eniwetok, A. cf. sociable 

Lemoine, in growth habit and cell size but has smaller 

and narrower sporangia and wider cells.

Age: Miocene.

Locality: Eniwetok F-l, depths 2,000 ft (core), 2,662-2,687 

ft (core) ; E-l, 1,718-1,740 ft (cuttings).

Figured speoimens: Holotype USNM 51424, 51425.

Archaeolithothamnium lauense Johnson and Ferris

Plate 267, figure 8

ArchacolithotJiamnion lauensum Johnson and Ferris, 1950,

B. P. Bishop Mus. Bull. 201, p. 11, pi. 1, figs. A, D. 

ArcJiaeolitlwtJiamniuni lauense Johnson and Ferris. Johnson, 

1957, U.S. Geol. Survey Prof. Paper 280-E, p. 218, pi. 46, 

fig. 7.

Description.—Thallus irregular crust as much as 15 

mm thick. Hypothallus poorly developed consisting of 

few curved rows of cells that attain length of 20/x and 

width of 12/X-13/X. Perithallus forms compact tissue 

composed of well-defined vertical rows of cells with 

thin cross partitions. Cells 12/X-15/X by lO/x-13/x. 

Sporangia abundant, ovoid or elliptical, large, measuring 141/X-195/X high and 75/x-lOO/x in diameter.

Remarks.—In appearance, structure, and dimensions of cells and sporangia, the Eniwetok specimens 

agree with the type although they developed a slightly 

thicker crust.

Age: Miocene.

Locality: Eniwetok F-l, depth about 2,675 ft (core).

Figured specimen: M-5, USNM 51426.

Archaeolithothamnium marshallensum Johnson n. sp.

Plate 267, figure 5; plate 269, figure 3 

Description.—Thallus crustose, normally thin. Hypothallus 1-1.3 mm thick composed of horizontal to
918 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

curved rows of cells 9p-19ju long and 7^-11^ wide. 

Perithallic tissue fairly regular, transverse cell rows 

slightly more conspicuous than horizontal cells which 

are 8ju-13ju, long and 6ju,-13ju, wide. Sporangia ovoid, 

76/J-96/* high and 44^-63^ wide.

Remarks.—In cell dimensions and size of sporangia 

this form closely resembles A. A-uboiensis Ishijima, but 

differs in having regular instead of contorted perithallic tissue, and in shape and arrangement of sporangia.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,725-1,995 ft (core). 

Figured specimens: F-l-5-1, holotype USNM 51427; F-l-5- 

35, USNM 51428.

Archaeolithothamnium eniwetokensis Johnson n. sp. 

Plate 267, figure 6; plate 268, figure 1

Description.—Thallus thin, crustose, surface irregular. Hypothallus 100^-135^ thick consisting of curved 

rows of rectangular cells 15/*-28/i, long and 10/x-15ju 

wide. Perithallic tissue fairly regular. Vertical cell 

rows slightly more pronounced than horizontal, but 

cells so regularly arranged as to produce nearly reticulate pattern in vertical section. Cells 14ju-18ju, by 10^- 

13/i. Sporangia small, round ovoid, 41^-51^ high and 

25^-30^ in diameter.

Remarks.—This species has smallest sporangia of any 

Miocene species yet described. In cell dimensions and 

size of sporangia it suggests A. cluunorrosum Johnson 

from the Eocene of Saipan but has much more rounded 

sporangia and more regular perithallic tissue.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 ft (core). 

Figured specimens: Holotype USNM 51429 (large) ; USNM 

51430 (large).

Archaeolithothamnium oulianovi Pfender

ArcJiae&lithothamnion oulianovi Pfender, 1926, Soc. espanola

historia nat. Bol., v. 26, p. 325, pi. 10.

Johnson. 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 

218, pi. 38, fig. 5; pi. 39, figs. 4. 5.

Description.—Very thin crusts which may grow 

superimposed. Tissue irregular. Hypothallus poorly 

developed (50ju,-90ju, thick) consisting of few layers of 

irregular cells. Basal-layer cells commonly oblique. 

Cells measure 9ju,-21/x, by 8/A-12/*. Perithallus rather 

irregular. Cells in wT ell-defined vertical rows but not 

regular horizontally. Cells 9^-12^ by 7/*-10,u. Sporangia oval to circular in section, 56ju-76/x by 32ju,-49ju, 

occurring in isolated clusters.

Remark.—Distinctive features of this species are 

irregular perithallic tissue more suggestive of Lithothamnium than normal Archaeolithamniuin and irregular arrangement of sporangia. Cells similar to those 

of type but show less range in size. They are similar to the material attributed to this species from Eocene 

of Saipan.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 3,655-3,988 ft (core).

Specimens: F-l-9-9, F-l-10-1.

Archaeolithothamnium puntiense Airoldi

ArcJiaeolithothamnion puntiense Airoldi, 1933, Palaeontographia 

Italica, Mem. Palaeont., v. 33, (new ser., v. 3), p. 83, 

pl. 7, fig. 1.

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 218, 

pl. 53, figs. 3, 4.

Description.—Thallus irregular crusts from 0.5-15 

mm thick. Hypothallus thin (0.03-0.1 mm thick), 

containing only a few curved layers of cells measuring 

5^-8^ by lOju-14^. Perithallus consists of fairly regular 

rows of cells, vertical partitions more conspicuous 

than horizontal. Cells rectangular, 8/*-14/* by 7ju-12,u. 

Suggestions of thin irregular growth zones. Sporangia abundant in well-defined layers, majority oval in 

section, some subquadrate with rounded corners. 

Sporangial cavities measure 62ju,-96ju high and 30ju,-59^ 

wide. One specimen shows slightly larger sporangia, 

80^-130^ high and 66^-72^ wide.

Remarks.—In growth habit and dimensions of cells 

and sporangia, Kita-Daito-Jima material closely resembles Airoldi's type material from Pleistocene of 

Somaliland. Ishijima's species Archaeolithothamnium 

megamiensis from Tertiary of Japan (Ishijima, 1933, 

p. 29) probably represents same species. Both papers 

were published about the same time (1933). Unfortunately, Ishijima's description was brief and generalized, 

being based on single fragment. It would be preferable to tie Kita-Daito-Jima species with Japanese material because of its geographic proximity, but Airoldi's 

species has a more solid basis than Ishijima's; so his 

name is applied. Cell dimensions and size of sporangia mainly same as Recent A. sibogae Weber van 

Bosse and Foslie (1904, p. 41-42), but they differ 

greatly in structure and growth habit. A. puntiense 

develops as thin crust, whereas A. sibogae forms a cluster of thick branches with tissue differentiated into 

medial hypothallus and perithallus.

Age: Pleistocene ( ?).

Locality: Kita-Daito-Jima, depth 16 ft (4.8 m) and 160 ft 

(48.7 m). 

Specimens: Tohoku University colln., slides 53 and 246.

Archaeolithothamnium schmidti Foslie

ArchaeolitJwthamnion schmidti Foslie, 1901, Bot. Tidsskr., v.

24, p. 16

Weber van Bosse and Foslie, 1904, Si&og'a-Expeditie Mon. 

61, p. 43, pl. 8, figs. 16-17

Description.—Thallus develops thin irregular crust, 

which forms rounded nodular mass 0.3—0.7 mm thick.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 919

Hypothallus thin, composed of slightly curved rows 

of rectangular cells, many nearly square. Dimensions: 

7/^-10/i long and 7/i-ll/* wide (average 9/* by 8/*). 

Perithallus formed of fairly regular rows of cells; 

horizontal partitions of tissue much stronger than vertical. Cells 9/^-10.5^ long and 5ju-10ju wide (average 10/* 

by 8.5/.).

Sporangia circular to subelliptical; widely spaced in 

rows in tissue; size variable as shown by following 

dimensions in microns.

45 by 52 46 by 70

48 by 78 52 by 64

37 by 73 52 by 57

Remarks.—Growth habit and cell dimensions fit 

closely descriptions of Recent A. schmidti Foslie from 

Indochina and East Indies, except that conceptacles 

of Funafuti specimens are slightly wider than in type.

Age: Pleistocene or Recent.

Locality: Funafuti, main boring, depth 691-698 ft.

Archaeolithothamnium cf. A. sociabile Lemoine 

Plate 267, figures 3, 4

Archaeolithothamnion sociabile Lemoine, 1939, Mat. Carte 

geol. de FAlgerie, ser. 1, Paleont. no. 9, p. 53, figs. 16, 17.

Description.—Plants crustose, thin, some growing 

superimposed to form irregular crusts. Hypothallus 

0.5-2 mm thick, formed of curved rows of cells 15ju-23ju 

long and 8/^-15^ high. Perithallus quite regular, horizontal layers almost as distinct as vertical rows. Cells 

rectangular, 10yu-15/x long and 8/x,-12/x, wide. Sporangia 

long ovoid, 100^-126/A high and 58/^-69^ in diameter, 

closely packed, forming lenses in tissue.

Remarks.—In appearance, growth habit, and cell 

dimensions Eniwetok form closely resembles A. sodabile described by Lemoine from Algeria but, has 

slightly larger sporangia and a somewhat greater development of the hypothallus.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,528-4,555 ft (core).

Figured, specimens: F-l-15-4 (1 and 2), USNM 51431, 51432.

Archaeolithothamnium cf. A. taiwanensis Ishijima 

Plate 267, figure 7

ArchaeoHthotliamnion, taiwanensis Ishijima, 1942. Taiwan Tigaku Kizi, v. 13, no. 4, p. 120 (2), fig. 2. 

Ishijima, 1954, Cenozoic and coralline algae western

Pacific, p. 18, pi. 1, fig. 5. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E,

p. 218, pi. 46, figs. 4-6.

Description.—Thallus rounded. Hypothallus 1-1.5 

mm thick of curved rows of cells llju-15/x long and 

6/x-9/x, wide. Perithallus fairly regular with cells 

13/x, long and 7/x-ll/x, wide. Sporangia 72/x, by 50^

Remarks.—Represented by single fragment in Eniwetok collections. Closely agrees with Ishijima's type 

from Formosa but has better developed hypothallus.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,718-1,740 ft (core).

Figured specimen: F-l-4-8 (1), USNM 51433.

Archaeolithothamnium sp. A 

Plate 267, figure 9

Description.—Thallus a thin irregular crust. Hypothallus 100^-150/x, thick composed of curved rows of 

small cells measuring 7/^-12^ by 7^-8^. Perithallus 

rather irregular, cells 7/^-11/x, by 6ju-8^. Sporangia 

48/^-60^ high and 30ju-36/x, in diameter.

Remarks.—Represented by a single specimen. Suggests A. oulianom Pfender in growth habit and general 

character of tissue. Sporangia slightly smaller, cells 

smaller and square in section rather than oblong, as in 

A. oulianom.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,528-4,553 ft (core).

Figured, specimen: CC-7, USNM 51434.

Division 2—Crusts with protuberances or short branches 

Archaeolithothamnium erythraeum (Rothpletz) Foslie

Plate 268, figures 2, 3

Lithothamniutn erythraeum Rothpletz, 1893, Bot. Centralbl.,

no. 14. 

Archaeolithothamnion erythraeum Foslie, 1900, K. norske

vidensk. selsk. Skr., no. 5, p. 8. 

Weber van Bosse and Foslie, 1904, Si&o^a-Expeditie Mon.

61, p. 38-41, pis. 5 and 6.

Description.—Thallus started as thin crust, then developed small mammillate protuberances. In 3 specimens in which thallus was observed, it measured 0.360 

mm, 0.385 nun, and 0.246 mm in thickness. Hypothallus poorly developed, consisting of only a few nearly 

horizontal rows of cells, rather irregular, square to 

rectangular, mostly long and narrow. Size range 

from lO/x-40/A long and 9ju-12/x, wide. Perithallus forms 

most of crust, composed of quite regular rows of cells 

from 14/^-20/x, long and 8/^-10/x, wide. Occasionally, a 

row of shorter cells sandwiched between rows of longer 

cells. Shorter cells nearly square and average 6^-9/A 

by 7/^-10/i. Sporangia normally long and oval but 

some nearly spherical, others irregular. They measure 

75^-90/x by 45^-55^.

Remarks.—Specimens studied badly recrystallized, 

and it was difficult to measure cells except in few local 

patches. General appearance, growth habits, and dimensions of cells and sporangia are same as in Recent 

specimens of this species from tropical Pacific.
920 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Age: Pleistocene or Recent.

Locality: Funafuti, slide 699, depth 748-763 ft; main boring, slide 703, depth 764 ft; slide 773, depth 891-899 ft. 

Figured specimen: British Museum slide 773.

Archaeolithothamnium cf. A. erythraeum (Rothpletz) Foslie

Description.—Fragment of crust with mammilated 

surface about 0.5 cm thick. Hypothallus poorly developed. Exact measurement of cells impossible because of recrystallization, but they approximate 

12//.-40JU, by lOju. Perithallus thick, layers of short approximately square cells alternate with several layers 

of long cells. Cells approximate 13ju,-19ju by Sju-lOju. 

Conceptacles elongate oval, in fairly regular rows in 

tissue; locally conceptacles are closely packed. Size 

95ft-119ju by 70/^-90^.

Remarks.—Represented by one badly recrystallized 

specimen. General appearance, growth habit, and cell 

dimensions fit modern A. enjthraefum, but conceptacles 

somewhat larger, more regular, and more closely 

spaced.

Age: Pleistocene.

Locality: Funafuti, main boring. British Museum slide 757, 

depth 867-874 ft.

Archaeolithothamnium aff. A. erythraeum (Rothpletz) Foslie 

Plate 268, figure 4

Arcliaeolithothamnion erythraeum, Weber van Bosse and 

Foslie, 1904. Siboga Expeditie Mon. 61, p. 39, pis. 5, 6.

Description.—Thallus crustose with rounded knobs 

or short stubby branches. Hypothallus not observed. 

Perithallic tissue compact, locally rather irregular, 

but in most cases with cells in fairly regular rows and 

layers. Cells rectangular ISju-lGju by 8^-12^. Sporangia oval to almost cylindrical, 63ju-86ju by 30ju-50/A.

Remarks.—Represented by only few fragments. 

Material strongly resembles Recent A. erythraeum, 

cells in same size range, but conceptacles of Eniwetok 

specimens smaller. Ishijima described a species from 

the Tertiary of Japan (1933, p. 29) as A. megamiemis 

that almost corresponds in dimensions with present 

species except for growth form. It also resembles A. 

taiwanensis Ishijima. Ishijinia's description so generalized that comparison is difficult. His species, however, appear to have smaller cells and conceptacles.

Age: Miocene.

Locality: Eniwetok, from cuttings collected from E-l at

depths of 2,340-2,660 ft but may have come from higher levels.

Figured specimen: 34, E-l, depth 2,650-2,660 ft, USNM 51435.

Archaeolithothamnium aff. A. saipanense Johnson

Archacolitlwtliamnium saipanense Johnson, 1957, U.S. Geol. 

Survey Prof. Paper, 280-E, p. 220, pi. 38, figs. 1-4, 6.

Description.—Thallus crustose, possibly with protuberances. Hypothallus about 120ja thick. Cell rows

llju-13ju wide. Cell lengths could not be measured because of poor preservation. Perithallic tissue compact 

and fairly regular with cells 12ju-14//, by 9ju-14ju. Sporangia large, ovoid, 145ju-165ju high and 96ju-100ju wide. 

Remarks. — Represented by single specimen. It closely resembles A. saipanense Johnson in growth habit 

and cell size but has appreciably larger sporangia, 

Sporangia largest observed in any Eocene ArcheoUthothamnium. It may represent new species, but until 

more and better material is available, it does not seem 

desirable to give it a new name.

Affe: Late Eocene.

Locality: Eniwetok F-l, depth 4,528-4,553 ft (core).

Specimen: DD-5, USNM 51436.

Archaeolithothamnium nummuliticum (Giimbel) Rothpletz

Plate 268, figure 6 ; plate 269, figure 2

Lithothamnion nummuliticum Giimbel, 1861, Geognostische

Beschreibung des bayerischen Alpengebirges und seines

Vorlandes, p. 654. 

Giimbel, 1871, Abhand. d. K. bay. Ak. Wiss., II Klasse,

v. 11, pt. 1, p. 27, pi. 1, fig. 2b. 

(Giimbel) Rothpletz, 1891, Deutsche geol. Gesell. Zeitschr.,

v. 43, p. 316, pi. 17, fig. 5. 

Capeder, 1900, Contrib. allo studio der Litfiothamnium

terzlari, Malpighia, p. 176, pi. 6, fig. 2. 

Archaeolithothamnion nummuliticum (Gumbel) Lemoine, 1917,

Bull. geol. Soc. France, ser. 4, v. 17, p. 247. 

Lemoine, 1927, Mus. nat. histoire nat. Bull. (Nov. 1927),

p. 546, fig. 1. 

Lemoine, 1934, Vestni. stat. Geolog. ustavu csl. rep., v. 9,

no. 5, p. 273. 

Lemoine, 1939, Mat. carte geol. de I'Algerie, ser. 1, Pal6ont.,

no. 9, p. 56.

Description. — Thallus crustose, developing protuberances or even short stubby branches. Hypothallus absent on specimens studied. Perithallus composed of 

rectangular cells 13ju-23ju, by 9/I.-14//, (commonly 

16ju,-23ju by 9^-12^) . In some cases, tissue regularly arranged ; in others irregular. In most areas vertical partitions more pronounced than horizontal. Sporangia 

large, ovoid to almost rectangular, measuring lOOju,-

Remarks. — Widely distributed species with long geological range. It has been described by many authors 

from western Europe, Mediterranean basin, and Near 

East. It is characterized by its unusual growth habit, 

relatively large rectangular perithallic cells, and large 

sporangia.

The several Eniwetok specimens have same growth 

habit, cell size, and length of sporangia. They differ 

in having somewhat wider sporangia (as much as 90/u, 

instead of 65ju) and more pronounced vertical cell rows 

than in specimens attributed to this species in Mediterranean region.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 921

Species suggests A. saipanense Johnson but lias appreciably larger perithallic cells.

Age: Late Eocene.

Locality: Eniwetok E-l-2-3, depth, 2,802-2,808 ft (core) ; 

F-l, 3,655-3,665 ft, and 4,197-4,222 ft (cores).

Figured specimens: F-l-9-2 (4) (large), USNM 40813; 

E-l-2-3 (2) (large), USNM 40810.

Archaeolithothamnium cf. A. hemchandri Rao

Plate 268, figure 7

Arcliaeolitliotliamnion Jiemcliandri Sripada Rao, 1943, Natl. 

Acacl. Sci. India, Proc., v. 13, pt. 5, p. 275, pi. 1, fig. 7.

Description.—Thallus encrusted with mammiliform 

protuberances, hypothallus absent, perithallus of rectangular cells showing fairly pronounced recalculated 

pattern and measuring ll/x-19yn by 8/*-12/x. Sporangia 

rounded ovoid 43/U-45/A by 48,^-65^.

Remarks.—Species represented by one specimen 

from Eniwetok material. It closely resembles type 

species described from lower Eocene of Assam but cells 

average larger and are slightly more irregularly arranged. A. hemchandri is distinguished from all other 

Eocene species of Archaeolithothamnium by its small 

cells and nearly spherical sporangia.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 3,655-3,665 ft (core).

Figured specimen: F-l-9-2 (2) (large), USNM 51437.

Archaeolithothamnium sp. B

Description.—Plant with short stubby branches, 

tissue of branches formed of rows of small nearly cubic 

cells so regularly arranged that they appear to be in 

layers. Cell walls forming both vertical and horizontal partitions are thin but clearly defined. Cells 

measure 8/*-ll/n by S/u-ll/*. Conceptacles unknown.

Remarks.—Represented in Eniwetok collection by 

two worn fragments of branches.

Age: Late Eocene.

Locality: Eniwetok E-l, depth, 2,730-2,740 ft (cuttings).

Division 3—Strongly branching forms 

Archaeolithothamnium aff. A. affine Howe 

Plate 269, figure 1

Archaoelithothamnion affine Howe, 1919, Carnegie Inst. Washington Pub. 291, p. 11, pi. 4, fig. 1; pi. 5, figs. 1-2.

Lemoine, 1939, Mat. Carte gSol. de 1'Algerie, ser. 1, Paleont, 

no. 9, p. 60, fig. 25.

Lignac-Grutterink, 1943, Geol.-mijnb. genootsch. Nederland 

en Kolonien Verb., Geol. ser. jagu 113, p. 286, fig. 1.

Description.—Strongly branching form with distinct 

medullary hypothallus and marginal perithallus. 

Branches 2-3 mm in diameter. Medullary hypothallus forms most of branch; composed of curved layers 

of rectangular cells 16^-2fy by ll/A-14^. There are suggestions of growth zones. In these zones transverse upward-growing cell rows more conspicuous than layers. 

Marginal perithallus is 2-3 mm thick, composed of cells 

ll/u-16/A by 9/u-lO/A.

Sporangia numerous, in regular rows in medullary 

hypothallus tissue; sporangia long and ovoid, some almost cylindrical; size 90yu-120yu by 34^-36^. Sporangia, 

in most cases, separated from one another by a few rows 

of tissue cells.

Remarks.—Very few branching species of Archaeolithothamnium with well-developed medullary hypothallus have been reported from Miocene. This 

form from Eniwetok most closely resembles A. affine 

described by Howe from Oligocene of West Indies, but 

has appreciably longer sporangia and more sharply separated hypothallus and perithallus.

Lignac-Grutterink reported material under this name 

from East Indies, but the Eniwetok specimen has longer 

sporangia and much more distinct marginal perithallus.

Specimen closely resembles the Recent A. timorense 

of tropical Pacific but has more nearly quadrate cells 

and longer sporangia. It probably represents an undescribed species but, with only one fragment available 

for study, it does not seem wise to describe it as such.

Age: Miocene.

Locality: Eniwetok E-l, depth 2,350-2,360 ft (cuttings).

Figured specimen: E-l, 2,350-2,360 ft, USNM 51438.

Archaeolithothamnium dallonii Lemoine

Plate 268, figure 5

Age: Miocene.

Looality: Eniwetok E-l, depth 2,350-2,360 ft (cuttings).

Figured specimens: F-l-9-2 (4) (large), USNM 40813.

Description.—Strongly branching form. Perithallic tissue regular with well-defined horizontal and vertical partitions. Cells 20^-24^ by 9/*-12^. Sporangia 

long oval to gourd shaped, 90/A-136/U by 54ju,-75^.

Remarks.—Represented by single well-preserved 

fragment from Eniwetok which resembles very closely 

Mme. Lemoine's type material from western Mediterranean. Only difference is that some of sporangia 

attain a slightly greater length in Eniwetok specimen.

This species closely resembles A. nummuliticum 

(Giimbel) Rothpletz except in growth form (strongly 

branching versus a crust with short stubby branches) 

and in having smaller sporangia.

Age: Late Eocene.

Locality: Eniwetok E-l, depth 2,802-2,808 ft (core).

Figured specimen: E-l-2-9 (large), USNM 51439.

Genus LITHOTHAMNIUM Philippi, 1837 

The thallus may be crustose or with erect branches 

growing from a basal crust. The tissue consists of a
922 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

hypothallus and a perithallus. A thin epithallus is 

present in living plants; it may or may not be preserved 

in fossils. Commonly, the hypothallus consists of 

loosely spaced horizontal rows of elongated cells that 

branch and curve upward at right angles to the substratum. The perithallus is composed of vertical infrequently branched cell rows, with the cells quadrate, 

rectangular, or ovate. Sporangial conceptacles have 

many openings or pores in the roof for the escape of 

spores. 

This genus is represented by a number of species in

the samples from Eniwetok, Kita-Daito-Jima, and 

Funafuti.

For convenience in study the species are grouped in 

three divisions based on the growth form: 

Division 1.—Simple crusts. 

Division 2.—Crusts with warty protuberances or short

stubby branches. 

Division 3.—Strongly branching forms.

The following table summarizes the characteristic 

features of each species of Lithothamnium described.

Measurements (in microns) and distribution of species of Lithothamnium

Species

Hypothallus cells

Length Width

Perithallus cells

Length Width

Conceptacles

Diameter Height

Locality Depth (feet) Age

Division 1.—Simple crusts

[Commonly thin; several may be superimposed]

sp- C... _ — -_._——--___--——_—-._—.—

16-26

11-21(34)

15-27

9-12

14-23

0—14

22-42

9-12

8-13

10-15

8-12

10-13

9-12

8-16

12-15

7-14

10-15

12-18

12-13

Q-ll

8-19

9-12

6-11

10-12

9-12

11-14

10-14

9-14

550-590

304-537

235-405

190

185-200

115-153

..... do...— ———

.....do.............

— ..do........ .....

.....do.............

-— do........ .....

— ..do... ..........

4, 528-4, 553

4, 500-4, 553

4, 528-4, 553

1, 718-2, 670

1, 978-2, 003

2, 662-2, 668

1, 740-2, 670

Do.

Do.

Do.

Do.

Do.

Division 2.—Crusts with warty protuberances or short stubby branches

7-11

10-24

9-16

14-30

12-14

10-12

6-8

8-13

9-11

6-14

8-14

12-18

6-8

6-11

6-10

8-16

223-242

500-750

578-807

122-143

275-298

Kita-Daito-Jima ..

Eniwetok F-l.....

0-173

0-800 0-16

1,978-2,003

Division 3.—Strongly branching forms

23-33 14-18 9-15 13-16 Eniwetok E-l_____ 2, 003-2, 008

Division 1—Simple crusts

Lithothamnium cf. L. abrardi Lemoine

Lithothamnium abrardi Lemoine, 1934, Czechoslovakia, Statni

Geol. tJstav, Vestnik r. 9, c. 5, p. 274, fig. 3. 

Lernoine, 1939, Mat. Carte g6ol. de 1'Algerie, ser. 1, Paleont.,

no. 9, p. 67.

Lithothamnium cf. L. abrardi Lemoine. Johnson, 1957, U.S. 

Geol. Survey Prof. Paper 280-E, p. 221, pi. 41, figs. 6, 7; 

pi. 42, figs. 1, 5.

Description.—Thallus thin crust with well-developed 

hypothallus and poorly to moderately developed 

perithallus. Hypothallus consists of curved rows of 

cells 16/i-26/x by 9/A-12/X. Perithallus of rectangular 

cells 12/x-15/x by 9/X-12/A. No conceptacles present.

Remarks.—In general appearance and in cell dimensions Eniwetok material agrees with specimens described under this name from Eocene of Saipan.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,528-4,553 ft (core).

Specimen: DD-2.

Lithothamnium crispithallus Johnson

Lithothamnium crispithallus Johnson, 1957, U.S. Geol. Survey 

Prof. Paper 280-E, p. 223, pi. 42, figs. 6-8.

Description.—Thallus thin curving crusts, apparently originally attached but later growing free. Hypothallus well developed, 90/i-170/x thick, consisting of 

curved rows of cells 11^-26/x (34/x) by 8/^-13^. Perithallus thin, irregular, thickening greatly around conceptacles; cells 7/i-14/i by 6/x-ll/x. Conceptacle chamber 55CV-590/* by 190/*.

Remarks.—Represented by a number of specimens. 

The Eniwetok specimens have longer perithallic cells 

than those described from Saipan.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,500-4,553 ft. (core). 

Specimens: CC7; F-l-15-13 (2) large; F-l-15-3 (2) large 

F-l-14-29 large.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 923

Lithothamnium cymbicrusta Johnson

LithotJiamnium cyinWcrusta Johnson, 1957, U.S. Geol. Survey 

Prof. Paper 280-E, p. 224, pi. 40, figs. 1, 6, 7; pi. 41, fig. 8.

Description.—Thallus thin regular crust about 300/j 

thick. Hypothallus well developed, forming most 

of crust. Hypothallus composed of rows of cells with 

fanlike arrangement, curving from center toward top 

and bottom; cells 15/^-27^ by 10/A-15/A. Perithallus 

thin, composed of regular rows of nearly square cells 

lO/A-15/x, by 10/A-12/A. Clusters of conceptacles occur 

in little knobs raised above general level of crust. Conceptacle chambers 304/A-537/A by 185/A-200/A.

Remarks.—Eniwetok specimens agree with material 

described from Saipan except for larger size of some 

conceptacles. The large f anlike hypothallus and knobs 

of conceptacles seem to be very characteristic features 

of the species.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,528-4,553 ft (core).

Specimen: DD-2.

Lithothamnium leptum Johnson and Ferris 

Plate 270, figure 7

Lithothamnion leptum Johnson and Ferris, 1950, B. P. Bishop 

Mus. Bull. 201, p. 13, pi. 2, fig. D.

Description.—Thallus thin irregular crust. Numerous thalli may grow superimposed to form an irregular 

mass. Hypothallus poorly developed or absent, at 

most only few rows of cells that measure 9jU,-12/>t by 

8/A-12//, (1-i/x,). Perithallus consists of rows of rectangular cells 12/A-18/* by 9ju-12/x,. Conceptacle chambers 

115/^-153^.

Eniwetok specimens closely agree with 

type material from Lau, Fiji. Also close to L. araii 

Ishijima from the Miocene of Japan.

Age: Miocene.

Locality: Eniwetok F-l depths 1,718-2,670 ft (cores).

Figured specimen: F-l-6-12, USNM 40799.

Lithothamnium sp. A 

Plate 269, figure 8

Description.—Thallus a thin irregular crust 200^- 

350/x, thick. Hypothallus plumose, 100/^-125/x, thick; 

rectangular cells 14/*-23/* by 10^-13/x,. Perithallus 

lOO/x.-200/x, thick; shows irregular growth zones of rows 

of rectangular cells 12^-13/x, by ll/x,-14^. Conceptacles 

unknown.

Remarks.—Form has about the same dimensions as 

L. bikiniensum Johnson from lower Miocene of Bikini 

but has well-developed rather plumy hypothallus and 

thicker crusts. Without knowledge of conceptacles of 

either species, they are considered as closely related but 

probably different.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 ft (core).

Figured specimen: F-l-5-12 (3), USNM 40800.

Lithothamnium sp. B 

Plate 270, figure 2

Description.—Thallus an irregular crust 300//.-500/-1 

thick. Hypothallus plumose, l75//,-200//, thick with local 

fanlike developments. Cells 9^-14/x, by 9^-12/x,. Perithallus relatively thin; cells 9/^-11^ by 10/^-14^. Conceptacles unknown.

Remarks.—Species closely related to L. araii Ishijima and L. leptum Johnson and Ferris but has welldeveloped plumy hypothallus.

Age: Miocene.

Locality: Eniwetok F-l, depth 2,662-2,668 ft. (core).

Figured specimen: F-l-6-28 (3), USNM 40801.

Lithothamnium sp. C 

Plate 269, figures 6, 7

Description.—Thallus an irregular crust 0.600— 

0.750 mm thick; well-developed hypothallus and perithallus. Hypothallus 150/^-250/>i thick, composed of 

curved rows of cells 22^-42/j by 8/*-16/*. Perithallus 

somewhat irregular, with noticeable growth zones; 

cells 8/^-19/j. by 9ju,-14ju. Conceptacles unknown.

Remarks.—This species differs from any previously 

described Miocene Lithothamnium in having unusually 

long hypothallic cells. Only L. lauenxe Johnson 

and Ferris has longer cells, but it has a poorly developed hypothallus in contrast to the thick conspicuous 

hypothallus of sp. C. Without a knowledge of the 

conceptacles, it does not seem desirable to give it a 

specific name.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,740-2,670 ft (cores).

Figured specimens: F-l-4-19 (1) large, USNM 40802; 

F-l-6-23 (4) large, USNM 40803.

Division 2—Crusts with warty protuberances or short stubby 

branches

Lithothamnium aff. L. aucklandicum Foslie 

Plate 270, figure 6

Litlioiliamnion aucklandicum Foslie, 1907, K. norske vidensk.

selsk. Skr., no. 6, p. 18. 

Litliotliamnium cf. L. aucklandicum Foslie. Johnson, 1957, U.S.

Geol. Surrey Prof. Paper 280-E, p. 224, pi. 53, fig. 9.

Description.—Thallus develops either as thick crust 

or more often as crust with warty protuberances. Hypothallus either poorly developed or only partly shown 

in the fragments observed. Hypothallic cells about 

7//.-11/* by 12^-14/A. Perithallus shows distinct irregular growth zones; cells 9/^-11/x, by 6/*-8/*. Conceptacles 

small but numerous, 223/^-242^ by 122^-143^. Some 

show presence of sporangia (pi. 270, fig. 6).
924 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Remarks.—The Kita-Daito-Jima material belongs to 

the same species as the specimen described by the writer 

from the Pleistocene of Saipan as L. cf. aucklandicum. 

It closely resembles the Recent L. notatum Foslie from 

Japan but has slightly larger conceptacles. Unfortunately, Foslie's description is brief, rather vague, and 

based on external structure, so clear comparison cannot be made.

Age: Pleistocene (?).

Locality: Kita-Daito-Jima core, depth 53 ft (16m).

Figured specimen: Tohoku University colln., slide 124.

Lithothamnium funafutiense Foslie 

Plate 270, figure 1

Lithothamnion funafutiense Foslie, 1900, K. norske vidensk.

selsk. Skr., no. 1, p. 5-6.

Foslie and Printz, 1929, K. norske vidensk, selsk. Museet, 

Mon., p. 41, 56, pi. 12, fig. 3^.

Description.—Thallus a thin irregular crust 0.125- 

0.600 mm thick. In some places several thalli superimposed to form crustose mass. Hypothallus moderately 

developed (often about 155ju, thick) ; rows gently to 

strongly curved. Cells rectangular, some rounded, 24ji*- 

35/x, by 13/X-15/X. Perithallus thin to moderately developed (150/X-320/X, thick). Cells square to slightly 

rectangular, 13/x-15/x, by 10ju-15/x. Conceptacles not 

present.

Remarks.—Foslie discusses this form in two papers 

but does not give a clear description, particularly with 

regard to range in cell dimensions. These specimens fit 

perfectly his description as to growth habit and general appearance of tissue. They show greater size 

range of cells than given by Foslie, but closely approximate his measurements. In general, core specimens have somewhat longer hypothallus cells and 

slightly wider perithallus cells. This might result from 

slightly oblique section. This above description based 

on several fossil specimens in two British Museum 

slides (534 and 726) . Crusts similar in appearance observed in number of other slides but slides too thick or 

material too recrystallized to permit accurate cell measurement.

Age: Pleistocene.

Locality: Funafuti, main boring, depth 452-798 (possibly 

880) ft. 

Figured specimen: British Museum slide 534.

Lithothamnium cf. L. nitidum Foslie 

Plate 270, figures 3, 4

Lithothamnion nitidum Foslie, 1901, K. norske. vidensk. selsk

Skr., no. 3, p. 4.

Foslie and Printz, 1929, K. norske. vidensk. selsk. Museet. 

Mon., p. 44, 54, pi. 6, fig. 10.

Description.—Thallus crustose, thin, probably warty, 

0.9-1.4 mm thick. Hypothallus absent or very poorly

developed; when present, appears to consist of only few 

irregular cell rows; cells 6/u,-8/A by 9/x-16/x. Perithallus 

of compact rectilinear rows of cells; cells rectangular 

6/x-lO/x, by 8/X-14/X. Conceptacles large, flattened. Concept acle cavities 578/X-807/X by 275/^-298/x.

Remarks.—In growth habit, character, and size of 

conceptacles and perithallic cells this form agrees with 

Foslie's description of L. nitidum from Japan. However, in Foslie's species the hypothallus better developed and contains larger cells. The Kita-Daitd-Jima 

specimens are closely related to L. funafutiense Foslie 

but have much smaller hypothallic cells.

This species was observed in a number of slides from 

Kita-Daitd-Jima. Most of the material is considerably 

recrystallized.

Age: Probably Pleistocene.

Locality: Kita-Daito-Jima. Surface material and depth 16 

ft (5 m).

Figured specimens: Tohoku University colln., slide 53, and 

Aoki colln., slide 196 (1).

Lithothamnium cf. L. mirabile Conti

Lithothamnion mirabile Conti, 1943, Palaeontographia Italica 

Mem. Paleont., v. 41 (new ser. v. 11), p. 43^4, pi. 5, fig. 

2; pi. 8, fig. 2.

Lithothamnium cf. L. miraMle Conti. Johnson, 1957, U.S. Geol. 

Survey Prof. Paper 280-E, p. 225, 48, fig. 3.

Description.—Thallus a thick irregular crust. Hypothallus well developed with curved rows of cells 

measuring 14/,1-30/x, by 8/x-13/x. Perithallus shows irregular growth zones; cells rectangular 12/x-18/x by 8p16/x. No conceptacles observed.

Remarks.—The Eniwetok specimens appear to belong to the same species as the material described from 

Saipan under this name. They agree with Conti's 

description except for having a slightly greater range 

in size of the hypothallic cells.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 ft (core). 

Specimens: 3-7 and K-3.

Division 3—Strongly branching forms 

Lithothamnium sp. D 

Plate 269, figures 4, 5

Description.—Long relatively slender branches 

formed of large medullary hypothallus surrounded by 

a narrow perithallus. .Medullary hypothallus formed 

of well-defined rows of rounded cells; rows curve toward margins at first gently, then sharply, to merge 

into perithallus. Hypothallic cells 23^-33/x, by 14/x-18/x. 

Perithallus cells 9/x-15/x by 13/X-16/A. Conceptacles unknown.

Remarks.—Represented in Eniwetok material by several fragments of branches. Cell dimensions of this
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 925

species differ appreciably from any branching Lithofhamnmm previously described from Miocene. However, without more material and knowledge of conceptacles, it does not seem wise to give it a specific name.

Age: Early Miocene.

Locality: Eniwetok E-1, depths 2,003-2,028 and 2,802-2,808 ft 

(core). 

Figured specimens: E-l-1, USNM 40922; E-l-2, USNM 40804.

Genus MESOPHYLLUM Lemoine, 1928

Description.—Structurally this genus lies between 

Lithothamnium, and LithophyUum. Tissue resembles 

that of latter, with hypothallus commonly coaxial and 

a perithallus composed of well-defined layers of cells. 

In most cases, perithallus and tissue of branches show 

pronounced irregular growth zones. Conceptacles have

numerous apertures similar to those of Lithothamnium.

Genus includes crustose and branching forms.

Known geologic range of Mesophyllum from Eocene 

to Kecent, with greatest development during Miocene 

time.

Kecent species live in littoral zone from just below 

tide level to depths as great as 175 feet; commonly 

found at depths of 30 to 100 feet.

For convenience in study, species arranged into three 

divisions based on growth habit.

Division 1.—Simple crusts.

2.—Short stubby branches.

3.—Strongly branching forms.

Following table gives dimensions and distribution 

of species identified.

Measurements (in microns) and distribution of species of Mesophyllum

Species

Hypothallus cells

Length Width

Perithallus cells

Length Width

Conceptacles

Diameter Height

Locality Depth 

(feet)

Age

Division 1.—Simple crusts

[Commonly thin; several may be superimposed]

Mesophyllum cf. M. arakuraensislshiiitnn.-..- 15-24 7-9 7-9

10-11

11-18

8-9

9-11

7-14

315-360

647-780

180-210 Eniwetok F-l......—

—— do—— __._——— . —. _do— „—— — —

2, 662-2, 687

1, 978-2, 003

1, 718-2, 003

Do.

Do.

Division 2.—Crusts with short stubby branches

20-26

23-28

13-27

7-9

10-13

7-12

13-17

12-14

8-16

7-12

6-8

7-14

9-10 360-630

238-356

120-200

140-180

... -.do... ... — „— —

..... do... ..... .... ——

20-30

1, 978-1, 995

2, 662-2, 687

3,052-3,055

Do.

Division 3.—Strongly branching forms

13-25

12-25

5-8

8-12

12-22

12-22

9-14

5-8

290-350 175-190 ——do—————— —

1, 718-1, 740

20-30

736-748

Division 1—Simple crusts

Mesophyllum cf. M. arakuraensis Ishijima

Plate 270, figure 5 ; plate 271, figure 1

Mesophyllum araJcuraensis Ishijima, 1954, Cenozoic coralline 

algae, western Pacific, p. 33, pi. 13, figs. 3-4.

Description.—Thallus small, irregular, crustose. 

Hypothallus coaxial, 150/A-400/A thick, of curved rows 

of rectangular cells 15//.-30//, by 7/i-13/i,. Perithallus 

contains irregular zones of layers of nearly square cells 

7/A-9/A by 8/*-9/A. Conceptacles small but high with 

multiple apertures. Size of conceptacle chambers 

350^-190/A, 350/A by ISO/*, 479/* by 236/A.

Remarks.—Represented by one fairly well preserved 

specimen and a few badly recrystallized examples. 

Specimens closely resemble Ishijima's material from 

lower Miocene (Burdigalian) of Japan but differ in 

having slightly shorter hypothallic cells.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 and 2,662-2,687 

ft (core).

Figured, specimens: F-l-5-11 (2) large, USNM 40805; 

F-l-6-18 (3), USNM 40806.

Mesophyllum eniwetokensum Johnson n. sp. 

Plate 272, figure 4

Description.—Thallus a very thin irregular crust; 

many thalli may grow superimposed to develop nodular mass. Hypothallus absent or consisting of only 

few layers of cells. Perithallic cells rectangular, 10/*- 

14/A by 9/A-ll/A. Conceptacle chambers large, 647/A-780jw 

by 200/A-210/*.

Remarks.—Mesophyllum eniwetokensum belongs to 

same group of genus as M. koritzae and M. Sancti 

Dionysii, which Lemoine (1939) found so abundantly 

developed in the Miocene of Algeria. It closely resembles M. Sancti Dionysii in growth habit, size of peri-
926 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

thallic cells, and large size of conceptacles. It differs 

from that species, in however, that hypothallus is 

poorly developed or absent. Both species have large 

many apertured conceptacles but, whereas high and 

strongly arched in M. Sancti Dionysii, they are relatively low and flat topped in M. eniioetokensum.

Age: Miocene.

Locality: Eniwetok F-l depth 1,978-2,003 ft (core).

Figured specimen: F-l-5-39 (3) holotype USNM 40807.

Mesophyllum sp. A 

Plate 271, figure 3

Description.—Thallus an irregular crust or plate. 

Hypothallus moderately coaxial, 180^-350^ thick; cells 

rectangular 15/^-38/x by lO/i-lfyu,. Perithallus shows irregular growth zones, 5 to 8 layers of cells in each zone. 

Cells rectangular, ll/x-18/x by 7/x-14/x. Conceptacles unknown.

Remarks.—A number of specimens of this species 

were observed. It differs in cell dimensions from previously decribed Miocene species. Without knowledge of 

conceptacles, it does not seem desirable to give it specific 

name.

Age: Miocene.

Locality: Eniwetok F-l, depths 1,718-2,003 ft (cores).

Figured specimen: F-l-5-12 (2), USNM 40808.

Division 2—Crusts with short stubby branches 

Mesophyllum erubescens (Foslie)

Plate 272, figure 6

Lithothamnion erubescens Foslie, 1900, K. norske. vidensk.

selsk. Skr., no. 5, p. 9. 

Weber van Bosse and Foslie, 1904, tfifto^a-Expeditie Mon.

61, p. 31-36, fig. 15-16, pi. 3, fig. 20. 

Mesophyllum erubescens (Foslie) Lemoine, 1928, Soe. bot.

France Bull. 5th ser. v. 75. P. 252.

Description.—Thallus a thin crust with thick stubby 

branches. Tissue of branches mainly medullary 

hypothallus though marginal hypothallus clearly developed. Tissue tends toward lenticular growth zones. 

Medullary hypothallus growth zones of 6-10 rows of 

rectangular cells; cells 20,/i-26//, by 7/x-9/x Perithallus 

cells square to rectangular, 13/x-l7/x by 7/A-12//, Conceptacles not present.

Remarks.—A widely distributed Recent species in the 

Pacific area. To judge by Foslie's several discussions it 

occurs in a number of growth forms and shows considerable range in cell dimensions.

The specimen studied agrees with Foslie's description.

Age: Pleistocene or Recent.

Locality: Funafuti, main boring, depth 20-30 ft.

Figured specimen: British Museum slide 615.

Mesophyllum japonicum Ishijima 

Plate 271, figure 2

Mcsophyllvm japonicum Ishijima, 1954, Cenozoic coralline algae 

western Pacific, p. 32, pi. 12, figs. 1-5; pi. 13, fig. 1.

Description.—The plant forms an irregular crust 

from which arise short stubby branches. Hypothallus 

coaxial with cells 23/^-28^ by 10//,-13//,. Tissue of perithallus and branches shows strong irregular growth 

zones, each consisting of layers of rectangular cells 

15/4-20//, by 6/x-S/A. No conceptacles present.

Remarks.—The structure, appearance, and cell dimensions agree closely with Ishijima's description and 

illustrations but the perithallis cells of the Eniwetok 

specimens average a little smaller.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-1,985 ft (core).

Figured specimen: F-l-5-1, USNM 40809.

Mesophyllum cf. M. savornini Lemoine 

Plate 271, figure 4

Mesophyllum savornini Lemoine, 1939, Mat. Carte geol. de

FAlgerie, ser. 1, Paleont, no. 9, p. 83, figs. 43-46. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 227, 

pi. 52, fig. 8.

Description.—Thallus develops crust, bearing short 

stubby branches that show strong growth zones. Each 

composed of layers of rectangular cells. The cells 

measure 12ju,-14//, by 7/x-14/x. Conceptacle chambers 

large, relatively low, and flat on top. Chambers 360/x630/i by 120/1-200/i.

Remarks.—Represented by several fragments of 

branches. The character of tissue, cell dimensions, 

and large size of conceptacles agree with those of Lemoine's type, and with specimens described by author 

from the Miocene of Saipan.

Age: Miocene.

Locality: Eniwetok F-l, depth 2,662-2,687 ft (core).

Figured specimen: N-2, USNM 40944.

Mesophyllum robustum Johnson n. sp. 

Plate 271, figure 6

Description.—Thallus a thick irregular crust, probably with rounded protuberances. Well-developed 

coaxial hypothallus 200/x-260/x thick. Hypothallic cells 

13ju-27ju, by 7ju-12ju. Perithallus consists of irregular 

growth bands, which may appear lenticular in section. 

Cells 8/A-16/A by 7ju,-10//,. Conceptacles small but highly 

arched. They measure 356/x by 169/x, 301ju, by ISO/*, 

238ju, by 141/A. Some traces of sporangia in conceptacles. 

Sporangia show heights of 33ft-55/A and diameters of 

26/1-40/t (3(V).

Remarks.—Species closely resembles M. heteroclitum 

Lemoine in cell dimensions and size of conceptacles but
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 927

has better developed coaxial hypothallus; the hypothallus of M. Jieteroclitum consists of few horizontal 

layers of cells very regularly arranged. M. robustum 

also closely resembles Lithothamnium camarasae 

Pfender but differs from it also in character and development of hypothallus.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 3,052-3,055 ft (core).

Figured, specimen: F-l-7-7 (2) large, Holotype USNM 40812.

Division 3.—Strongly branching forms 

Mesophyllum sp. B 

Plate 272, figure 5

Description.—Plants with long narrow spines or 

branches that are composed of arched layers of rectangular cells arranged in pronounced growth zones; 

each zone with 6 to 12 layers of cells; cells measure 12/A-22/A by 9/t-14/t. Conceptacles unknown.

Remarks.—Represented by several worn fragments. 

They differ from any branching Miocene species hitherto described from Pacific. Nearest described species 

M. commune Lemoine from Miocene of Algeria. Eniwetok species has slightly larger cells. Better specimens and knowledge of conceptacles needed before 

naming species.

Age: Miocene.

Locality: Eniwetok F-l, depth 1.718-1,740 ft (core).

Figured specimen: H2, USNM 40811.

Mesophyllum cf. M. australe (Foslie)

Lithothamnion coralloides f. australis Foslie, 1895, K. norske

vidensk. selsk. Skr., no. 2, p. 9. 

Lithothamnion australe Foslie, 1900, K. norske. vidensk. selsk.

Skr., no. 5, p. 13. 

Weber van Bosse and Foslie, 1904, $i&o#a-Expeditie Mon.

61, p. 24-29, figs. 10-12, pi. 2, figs. 10-51. 

Mesophyllum australe (Foslie) Lemoine, 1928, Soc. bot. France

Bull. 5th ser. v. 75, p. 252.

Description.—Thallus crustose with short stubby 

branches. Hypothallus moderately developed coaxial; 

cells 13/X.-25/A by 5//,-8/A. Perithallus composed of fairly regular rows of cells measuring 12/J-22/J by 5/A-8/A. 

Conceptacles absent.

Remarks.—Several fragments probably belonging to 

this species, or one closely related to it, were observed. 

Cells slightly longer than those of type but Foslie referred to L. australe as a highly variable form. Without conceptacles, an exact determination cannot be 

made.

Age: Pleistocene or Recent.

Locality: Funafuti, depths 20-23 ft and probably from depth 

957 ft. _ 

Specimens: British Museum slides 598, 611, 615.

584500 O -61 -3

Mesophyllum pulchrum (Foslie) 

Plate 271, figure 5

Lithothamnion pulchrum Foslie, 1901, K. norske. vidensk. selsk.

Skr., no. 3, p. 3. 

Weber van Bosse and Foslie, 1904, $i&o0a-Expeditie Mon.

61, p. 36-38, fig. 18, pi. 4, 

Mesophyllum pulchrum (Foslie) Lemoine, 1928, Soc. bot. France

Bull. 5th ser. v. 75, p. 252.

Description.—Thallus massive, branching, represented by fragments of thick branches. Basal hypothallus missing. Medullary hypothallus shows distinct rather regular cup-shaped growth zones. Cells 

appear rounded rectangular, longer than wide. Recrystallization prevents accurate cell measurements, 

but they are approximately 12/^-25/A by 8/A-12/A. Perithallus not observed around margins of branches. 

Three measured conceptacles gave diameters of 290/A35(V and heights of 175/*-190/*.

Remarks.—Specimen badly recrystallized. Growth 

habit and general appearance of tissue suggest that 

dimensions of cells and conceptacles of this species fall 

within dimension range of Recent examples from East 

Indies.

Age: Pleistocene.

Locality: Funafuti, main boring, depth 736-748 ft.

Figured specimen: British Museum slide 688.

Genus LITHOPHYLLUM Philippi, 1837

In this genus thallus is polystromatic, forming a 

crust or crust-developing protuberances or erect 

branches; differentiated into hypothallus, perithallus, 

and epithallus. Hypothallus is several to many layers 

thick, commonly coaxial. Hypothallic cells are mostly 

horizontally elongated. The perithallus usually is 

thinner than the hypothallus with cells typically isodiametric but sometimes elongated. The epithallus is 1 to 

4 layers thick, cells flattened parallel to the outer surface. It is seldom calcified; hence is rarely observed 

on fossil material. The conceptacles have a single large 

pore.

Litliophyttum is abundantly represented in the collections studied both in number of species and of individuals.

For convenience in study, the species are arranged 

into three divisions based on the growth habit.

Division 1.—Simple crusts.

2.—Crusts with warty proturbances or short 

stubby branches.

3.—Strongly branching forms.

The following table gives the dimensions and distribution of the species identified.
928 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Measurements (in microns) and distribution of species of Lithophyllum

Species

Hypothallus cells

Length Width

Perithallus cells

Length Width

Conceptacles

Diameter Height

Locality Depth 

(feet)

Age

Division 1.—Simple crusts

[Commonly thin; several may be superimposed]

12-30

14-22

16-25

10-18

14-18

10-14

5-7

15-20

8-14

9-11

R 1 1

15-76

8-9

27-43

Q— 9fi

OAQQ

8-15

7-11

8-11

Q in

9-17

9-12

8-16

7-14

7-10

7-8

8-10

27-83

7-11

17-30

5-7

1 Q_OK

125-170

225-447

185

208-246

153-171

36-55

67-102

81

101-109

89-97

Kita-Daito— — — —

..— do.—....—— —

Eniwetok F-l. .. ..— .

-..-do..-..—. .... ... -

Kita-Dait5— —— ——

Eniwetok K-l. .......

Eniwetok F-l___— ...

Kita-Dait5- Jima ......

—— do... __————

--— do......... — .... -

-...do..— ............

25-383

180

1,975-2,000

0-220

400

1,000

1, 978-2, 003

30

30

23-396

393

Do.

Do.

Do.

Pleistocene(?).

Do.

Division 2.—Crusts with warty protuberances or short stubby branches

12-16 30-45 12-22 8-10 161-235 60-78

90-160

Kita-Dait5-Jima. . . .. (')

2,655

Division 3.—Strongly branching forms

sp. B__ ......................................

28-65

Q— 33

20-41

30-36

10-17

7-14

(V_i e

11-30

8-16

9-17

7-15

9-13

10-15

315-375 160-250 Eniwetok F-l— ------

do

1, 720-2, 000

2, 100-2, 680

37-347

1, 978-2, 003

2, 690-2, 700

495

Miocene.

Do.

Do.

1 Surface.

Division 1—Simple crusts 

Lithophyllum acanthinum Foslie

Plate 273, figure 1

Lithophyllum acanthinum Foslie, 1907, K. norske. vidensk. 

selsk. Skr., no. 6, p. 26.

Description.—Thallus a crust 2-5 mm thick. Hypothallus coaxial; cells rectangular 18ju,-25/i by 8,u-14ju, 

Perithallus thin, cells rectangular, measuring 8/x,-15/x, 

by 7^-14^. No conceptacles present.

Remarks.—Represented in Kita-Daito-Jima collection by number of poorly preserved fragments, all infertile. Growth habit and cell dimensions agree with 

Foslie's description of L. acanthinum from central 

Japan although some of perithallic cells attain greater 

length.

Age: Pleistocene and possibly late Pliocene.

Locality: Kita-Daito-Jima core, depth 24 ft (7.5 m) and 

380ft (115m).

Figured specimen: Tohoku University colln., slide 656; slide 

43, not figured.

Lithophyllum hanzawae Johnson n. sp.

Plate 272, figures 2, 3 

Description.—Irregular crust 1.45-2.10 mm thick.

Hypothallus composed of cell rows curving up and 

down from center. Walls of cell rows clearly defined; 

walls between cells in row thin and obscure. Cells 9,u12/A by approximately 12^-30/A. Perithallus of regularly arranged cell rows; cells 7ju,-10/* by 7^-1 I/A. Conceptacles abundant, small, cavities measuring 125/*- 

170/* by 36^-55/x, high. Tops slightly arched and perforated by one large pore.

Remarks.—This species belongs to small group of encrusting Lithophyllum characterized by unusually 

small size of perithallic cells and conceptacles. It is 

closely related to Foslie's highly variable L. yendoi, 

but differs by having a different type of hypothallus, 

which is more strongly developed, and in having smaller conceptacles and slightly larger cell dimensions.

The species is named for Dr. Shoshiro Hanzawa of 

the Institute of Geology and Paleontology of Tohoku 

University who carefully studied the Kita-Daito-Jima 

cores, described the Foraminifera (Hanzawa 1940-41), 

and assisted in the present restudy.

Age: Pleistocene(?).

Locality: Kita-Daito-Jima core depth 53 ft (16 m).

Holotype: Tohoku University, Aoki colln. slide 141.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 929

Lithophyllum johnsoni Ishijima

Lithophyllum johnsoni Ishijima, 1954, Cenozoic coralline algae 

western Pacific, p. 42, pi. 25, fig. 4; pi. 26, figs. 1-3; pi. 

27, fig. 3.

Description.—Thallus crustose, thin; well-developed 

coaxial hypothallus and moderately developed perithallus. Hypothallic cells 14/x,-22/A by 9/A-llju. Perithallic 

cells small, rectangular to square in section, measuring 

8/a,-ll/x, by 7^-8/A. Conceptacles unknown.

Remarks.—The Eniwetok material fits Ishijima's species from the Miocene of Japan. Represented by a 

number of specimens in the Eniwetok collection.

Age: Miocene.

Locality: Eniwetok F-l, 1975-2,000 ft (core).

Lithophyllum cf. L. lingusticum Airoldi 

Plate 272, figure 1

Lithophyllum lingusticum Airoldi, 1932, Paleontographia Italica 

Mem. Paleont, v. 33 (new ser., v. 3), p. 72-73, pi. 12, figs. 

2-3.

Description.—Thallus a thin crust. Hypothallus coaxial, 160ju-25(V thick; cells 16^-25^ by 8/x-ll/x. Perithallus thin, 45^-75/A thick, of nearly cubic cells measuring 8/A-KV on a side. Conceptacles unknown.

Remarks.—No Eocene species of Lithophyllum with 

corresponding cell dimensions has been described previously. The closest described species is L. lingusticum 

Airoldi from the Oligocene of Somali which develops 

as a thin crust with short branches and has cell dimensions about the same as the Eniwetok specimens.

Age: Late Eocene.

Locality: Eniwetok F-l, 3,655-3,665 ft (core).

Figured specimen: F-l-9-9, USNM 40814.

Lithophyllum megacrustum Johnson and Ferris 

Lithophyllum megacrustum Johnson and Ferris, 1950, B. P.

Bishop Mus. Bull. 201, p. 16, pi. 7, figs. D, E. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 228,

pi. 54, fig. 8; pi. 55, fig. 1.

Description.—Plant has thick crust as much as or 

more than a centimeter thick. In some cases several 

superimposed thalli form crust. Hypothallus absent or 

slightly developed; commonly consists of single row of 

oblique cells, at most of only few rows of long cells; 

cells measure 6^-18/A by 12/^-76/A, commonly 11/A-16/A by 

28/A-48/A. Perithallus consists of regular rows of long 

rectangular cells with thick walls. Some areas are irregular, especially around Conceptacles. In some rows, 

cells are arranged obliquely to row walls and there may 

be suggestion of alternation of rows of cells of slightly 

different length. Cell walls distinct and thick; cells 

show an unusual size range, measuring 8/A-18/A by 21/A86/x,, commonly 9/A-14/A by 31/A-54/A. Conceptacle chambers 300/A-447/A by 67/^-140/x.

Sample

124——————— — ———

176—— — ——— — —

176————— ——— — —

25.———— — —— —— —

19— ———— — — — —

59..———— ——————— .

60— —— — — — — —

246—— ——— ——— ———

Aoki II. ...............

Aoki II.. ..............

272— — — — — ———

361..——— ———— ——— .

718— — ————— ————

K-l....................

Slide 774——— ————

Depth 

(feet)

]

0

0

0

18

20

29

29

160

217

400

1,000

Hypothallus 

(microns)

Kita-Daito-Jima

12-16X21-25

10-14X40-62

11-18X39-80

8-9 X29-47

10-14X31-76

11-13X45-63

13-18X28-34

11-15X15-27

14-15X27-47

Eniwetok

7-14

Funafuti

Perithallus 

(microns)

10-14X41-68

9-12X21-25

9-12X37-82

9-14X27-42

11-14X22-36

9-12X34-42

8-12X30-61

9-14X38-83

11-18X34-54

9-17X40-44

9-14X31-37

8-12X27-46

14-15X31-48

7-14X40-50

10-15X41-50

Conceptacles 

(microns)

300H147X 81-98

425 X 92

320-403 X 67-91

278 X 92

385 X109

302-374 X 90-102

302-306X 76-93

225-323 X 73-89

356-383 X 86-88

430 X130

328 X 81

313-316 X 82-84

Detailed measurements of a number of specimens 

studied from Kita-Daito-Jima, Eniwetok, and Funafuti 

are as follows.

Remarks.—Most abundant species in the Kita-DaitoJima cores. It resembles modern Lithophylhim papillosum (Zan.) Foslie of Mediterranean and tropical 

Pacific but differs in forming much thicker crust and, 

in most cases, has a more regular tissue.

Age: Pleistocene and probably Recent.

Locality: Kita-Daito-Jima core, surface to depths of 220 ft 

(66 m). Funafuti core, depth 1,000 ft. Eniwetok core K-l, 

depth 400 ft.

Specimens: Tohoku University colln., slides 25 and 176, and 

Aoki II.

Lithophyllum cf. L. prelichenoides Lemoine

Lithophyllum prelichenoides Lemoine, 1918, Soc. geol. France

Bull., ser. 4, v. 17, p. 262, figs. 8, 9 [imprint date 1917].

Lemoine, 1939, Mat. Carte geol. de 1'Algerie, ser. 1,

Paleont., no. 9, p. 99, figs. 65-66, p. 107. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-B, p. 229, 

pi. 49, figs. 1-2.

Description.—Thallus a thin crust or irregular plate 

consisting of well-developed coaxial hypothallus and 

thin perithallus. Hypothallic cells 14/^-1 S/A by 8/A-9/*. 

Perithallic cells nearly cubic, 10/A-12//, by T/A-ll/*. Conceptacle cavity 185/A by SI/*.

Remarks.—In growth habit, structure, and cell dimensions Eniwetok specimens resemble this widespread 

Miocene species. They differ from typical L. prelichenoides only in having slightly smaller average size of 

hypothallic cells.

Age: Miocene.

Locality: Eniwetok F-l, 1,978-2.003 ft (core).
930 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Lithophyllum quadratum Ishijima 

Plate 273, figure 2

Lithophyllum quadratum Ishijima, 1954, Cenozoic coralline 

algae western Pacific, p. 37-38, pi. 22, fig. 5a, b; pi. 23, 

fig. 1^.

Description. — Thallus a thin crust commonly about 

0.5 mm thick ; several or many thalli may grow superimposed to form irregular flattened masses. Hypothallus thin and irregular; cells 10/*-14/i, by 27/*-43/*. 

Perithallus shows rectilinear pattern in section. Tissue may show irregular growth zones. Cells measure 

by 17^-30^. Conceptacle cavities 208^-246^ by

Remarks. — Characteristic features of this species, 

rectilinear pattern of normal perithallic tissue, relatively large size of perithallic cells, diameter of the conceptacles, and irregularly zoned appearance of sections 

of crusts. Kita-Daito-Jima specimens agree with 

Ishijima 's description and illustrations except in having somewhat narrower perithallic cells. Species 

closely related to the Recent species L. yessoense 

Foslie, differing only in having longer hypothallic 

cells.

: Pleistocene (?). 

Locality: Kita-Daito-Jima, core depth 29 ft (8.97 m). 

Figured specimen: Tohoku University colln., slide 63.

Lithophyllum samosense Foslie 

Plate 273, figures 5, 6

Lithophyllum samosense Foslie, 1906, K. norske vidensk. selsk. 

Skr., no. 2, p. 20.

Description. — Thallus a thin crust on other algae or 

objects. Crusts 0.3-0.6 mm thick. Hypothallus irregularly developed, apparently varying with irregularities in substratum; hypothallic cells 5^-7^ by 

9ju-15^. Perithallus shows irregular growth zones, 

cells 5^-7/* by 5/*-7^. Conceptacles small, shaped like 

lima beans, in section 153^-17l/* by 89^-97/*.

Remarks. — Foslie described two species of thin crustose Lithophyllum from Pacific, L. samoense and L. 

yendoi. These species differ only in cell dimensions 

and size of conceptacles. They appear to have much 

the same geographic range. Specimens from KitaDait5-Jima cores exactly fit Foslie's description of L. 

samoense but they are close to material from Saipan 

referred by writer to L. yendoi', the Kita-Dait5-Jima 

specimens have slightly larger conceptacles.

Age: Pleistocene (?).

Locality: Kita-Daito-Jima, depth 29 ft (8.97 m) . 

Figured specimen: Tohoku University colln., slides 61 and 

256.

Lithophyllum stefaninii Airoldi 

Plate 273, figures 3, 4

Lithophyllum stefaninii Airoldi, 1933, Palaeontographia Italica

Men. Palaeont, v. 32, supp. 1, p. 90, pi. 8, fig. 2. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 

228, pi. 54, fig. 4.

Description.—Thallus a thin crust with well-defined 

hypothallus and perithallus. Hypothallus moderately 

coaxial, cells oval to rectangular, measuring 9/*-ll/x. by 

Perithallus quite regular, cells rectangular 

by 13/*-25fi. No conceptacles present. 

Remarks.—Relatively common in Kita-Daito-Jima 

material. In growth habit, appearance of tissue, and 

cell dimensions this form agrees with Airoldi's description of material from Pleistocene of Red Sea region.

Age: Probably Pliocene-Pleistocene.

Locality: Kita-Daito-Jima core, depth 22 ft (7 m) and 396 

ft (120 m).

Figured specimens: Tohoku University colln., slides 62 and 

661.

Lithophyllum thikombian Johnson and Ferris

Plate 273, figure 7

Lithophyllum thikombian Johnson and Ferris, 1950, B. P. 

Bishop Mus. Bull. 201, p. 17, pi. 6, figs. B and D.

Description.—Thallus crustose, consisting of welldeveloped coaxial hypothallus and some perithallic 

tissue. Hypothallus 0.29 mm thick, composed of rectangular cells 15^-20/i by 24^-33^. Perithallus of regular layers of cells; cells 12^-14^ by 16^-27^. Conceptacles not present.

Remarks.—This species is represented by several 

abraded fragments in core. In general appearance of 

tissue and in cell measurements it agrees closely with L. 

thikombian described from Miocene of Lau, Fiji.

Age: Probably Miocene.

Locality: Kita-Daito-Jima core, depth 363 ft (110 m) and 389 

ft. (119 m).

Figured specimen: Tohoku University colln., slide 656.

Division 2—Crusts with warty protuberances

Lithophyllum okamurae Foslie

Plate 274, figure 1

Lithophyllum okamurae Foslie, 1909, K. norske vidensk. selsk. 

Skr., no. 2, p. 30-31.

Description.—Thallus a thick crust from which develop warty protuberances. Hypothallus poorly to 

moderately developed; cells rectangular 12^-16^ by 

30^-45^. Perithallus thick, showing some growth 

zones; cells square to oblong in section, measuring 12^- 

22/x by 8^-10^. Conceptacles abundant, small; cav-
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 931

ities measure 161/t-235ju, in diameter and 60/t-Y8/A high. 

Remarks.—Foslie described this as a species with a 

variety of growth forms from Japan and East Indies. 

Forms include warty crusts and nodular crusts with 

short thick branches. Specimens studied fit description.

Age: Pleistocene or Recent.

Locality: Kita-Daito-Jima, surface outcrops.

Figured specimen: Tohoku University colln., slide 176.

Lithophyllum sp. A

Description.—Thallus a thick crust or mammillated 

mass. Hypothallus not observed. Perithallus of 

small rectangular cells in poorly defined layers. Cells 

measure ll/t-Mju, long and 8/t-lOju, wide. Conceptacles 

small gently arched to nearly fiat on top. Conceptacle 

chambers measure 195/A-210/A in diameter and 90//,-16(V 

in height.

Remarks.—Represented in Eniwetok slides by two 

worn fragments. They differ from previously described Miocene species, but are too poorly preserved 

to use as base for a new species. The nearest described 

species is Lithophyllum irregularis Ishijima which, 

however, has much larger and flatter conceptacles.

Age: Miocene.

Locality: Eniwetok E-l, depth. 2,650-2,660 ft (cuttings).

Division 3—Strongly branching forms

Lithophyllum kladosum Johnson 

Plate 272, figure 7 ; plate 274, figures 4, 5

Lithophyllum kladosum Johnson, 1954, U.S. Geol. Survey Prof. 

Paper 260-M, p. 539, pi. 192.

Description.—Long slender branches composed of 

well-developed medullary hypothallus surrounded by a 

relatively thick marginal perithallus. Hypothallic cells 

oblong in section, arranged in arched layers. Cells 

show considerable range in size of different rows of 

same specimen, measuring 28^-65^ high and 10//.-17//, 

wide. Perithallic cells cubic, in layers nearly perpendicular to the layers of the hypothallus; cells measure 

10/A-23/A by 9ju,-lT^. Conceptacles marginal, highly 

arched. Conceptacle chambers measure 315/A-375//, in 

diameter and 160//,-250ju in height.

Remarks.—In general appearance, cell measurements, 

and all structural features Eniwetok specimens agree 

with material described from beds of same age in 

Bikini drill hole. In addition several fertile specimens 

obtained.

This species is most abundantly represented of all 

species studied from Eniwetok material. It was found 

in both drill holes F-l and E-l, in cores and in cuttings.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,720-2,000 ft (cores) ; E-l, 

deptlr2rt00-2,680 ft (cuttings). 

Figured specimens: USNM 40815, and 40816, and 40924.

Lithophyllum cf. L. kotschyanum (Unger) Foslie 

Plate 274, figures 2, 3

Lithophyllum kotschyanum (Unger) Foslie, 1909, K. norske

vidensk. selsk. Skr., no. 2, p. 34-36.

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 230, 

pi. 57, fig. 1; pi. 58, fig. 1.

Description.—Thallus a crust with thick stubby 

branches that contain thick medullary hypothallus and 

moderately to well-developed marginal perithallus. 

Medullary hypothallus built of curved layers of rectangular cells; considerable range in cell size both in 

different layers and in same layer from center to edge. 

Cells measure 9//.-33/A by 7/t-H/A, commonly 12/A-15/* by 

8//.-1 I/A. In some cases there appears a fairly regular 

alternation of several layers of long cells with several 

layers of short cells (plate 8, fig. 3). Marginal perithallus of well-defined cell layers, cells ll/A-30/* long 

and T/i-15/A wide, commonly ll///-20ju, by 9//.-11/A. Conceptacles rather flattened on top with large central 

aperture; cavities 401//,-512/A in diameter and 93/A-180/* 

high.

Remarks.—Foslie's Recent species is very variable 

form. He named five forms, which grade one into another. There is corresponding variation in cell size and 

structural detail, some showing alternating layers of 

long and short cells, some not. The species has been 

reported from Red Sea to Samoa. The author has collected it around Guam and Saipan. The Kita-DaitoJima material agrees with Foslie's description except 

for having larger conceptacles. The type material has 

Conceptacle diameters of 250/A-400/A, while our specimens show diameters from 401/A-512/*, commonly 401^- 

44CV.

Numerous specimens attributed to this species were 

observed in the Kita-Dait5-Jima core at depths ranging 

from 10 to 100 meters (30 to 320 ft); all were worn 

branches or fragments.

Age: Pleistocene (?).

Locality: Kita-Daito-Jima core, depth 35 ft (10.73 m) and 

345ft (105m). 

Figured specimen: Tohoku University colln., slide 73.

Lithophyllum profundum Johnson 

Plate 275, figure 5

Lithophyllum profundum Johnson, 1954, U.S. Geol. Survey Prof. 

Paper 260-M, p. 539-540, pi. 191, figs. 5-7.

Description.—Plant forms clusters of long relatively 

slender branches. Each branch consists of moderately 

wide medullary hypothallus and much narrower perithallus. Hypothallus of arched layers of rectangular 

cells 20/t-41/t long and 9/x-15/* wide. Perithallus formed 

of layers of small rectangular cells 8/A-16//, by 9/*-13/t. 

Perithallus shows growth zones. Conceptacle chambers 300/A-360/A in diameter and 190/*-225/t in height.
932 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Remarks.—The structure, growth habit, and cell dimensions agree with species described from Bikini, 

based on fragments of infertile branches. Eniwetok 

collections contain larger pieces which give better 

idea of growth habit, and they include some with 

conceptacles.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 ft (core) ; E-l, 

2,690-2,700 ft (cuttings). 

Figured specimen: F-l-5-42, USNM 40913.

Lithophyllum sp. B

Description.—Worn fragment of branch with welldeveloped medullary hypothallus of gently arched 

layers of rectangular cells 30/A-36/A long and 15/A-18/A 

wide. Most of marginal perithallus worn off. Perithallic cells nearly square, 9/x-15/x by lO/x-15/A, averaging 10/A-ll/A square in section. Conceptacles absent.

Remarks.—This form does not exactly fit description 

of any previously described Miocene species. Because 

no conceptacles are present and it is represented by 

only one specimen in Kita-Daito-Jima collection, it does 

not seem desirable to name it as new species.

Specimen resembles fragment found in Bikini core at 

depth of 2,040 feet (Miocene). It was described (Johnson 1954b, p. 541) under name of Goniolithon cf. G. 

frutescens Foslie. Growth habit and cell dimensions 

are similar. Bikini specimen shows mo-re pronounced 

growth zones than Kita-Daito-Jima specimen.

Aye: Miocene.

Locality: Kita-Daito-Jima core, depth 492 ft (150 m).

Genus GONIOLITHOtf Foslie, 1900

The genus GonioUthon is closely related to Lithophyllum, having the same type of hypothallus and 

conceptacles. It resembles Porolitlion in having numerous megacells in the perithallic tissue; however, 

these occur in small rows perpendicular to the outer 

surface, not in lenses parallel to the surface as in Porolithon. In many cases there are only 2 or 3 megacells in a group, one above the other. Today, the genus 

is represented in the tropical Pacific by a small number of widely distributed species.

Goniolithon frutescens Foslie

GonioUthon (Cladolithon) frutescens Foslie, 1900, K. norske

vidensk. selsk. Skr., no. 1, p. 9-10.

Goniolithon frutescens Foslie, 1900, The fauna and geography 

of the Maldive and Laccadive Archipelagos, p. 468, pi. 

35, figs. 5-6. 

Weber van Bosse and Foslie, 1904, $i&o0a-Expeditie Mon.

61, p. 53, pi. 10 figs. 10-11.

Foslie and Printz, 1929, K. norske vidensk. selsk. Museet. 

Mon., p. 30 pis. 48, 52.

Taylor, 1950, Mich. Univ. Studies, Sci. ser., v. 18, p. 123-124,

pis. 58-60. 

Johnson, 1954, U.S. Geol. Survey Prof. Paper 260-M, p.

541, pi. 195, figs. 1-2. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p.

231, pi. 59, fig. 4; pi. 60, fig. 3.

Description.—Fragments of long rather irregular 

branches. Medullary hypothallus and the marginal 

perithallus well developed. Medullary hypothallus 

thick; in section consists of slightly to strongly curved 

rows of rectangular cells 23/x-32/x long and 12/x-lS/* 

wide. Perithallus composed of rows of cells that are 

fairly regular except around groups of megacells; cells 

measure 12/x-22/x long and 12/x-lS/* wide; megacells 

20/t-31/t in diameter, normally little longer or little 

shorter than wide. No conceptacles observed.

Remarks.—Foslie described this species originally 

from specimens collected on the Recent reefs at Funafuti. This species is most abundantly represented form 

recognized in the Funafuti cores. It also occurs in appreciable abundance on the Recent reefs and in surface 

and near-surface material at Eniwetok. It grows on 

corals and as small clusters of branches on the bottom 

in the more protected areas of the reef flat behind the 

algal ridge.

Age: Recent and Pleistocene.

Locality: Funafuti, on the Recent reefs and in the main 

drill hole down to depths of 950 ft; Eniwetok, Recent reefs and 

in K-l from surface to depth of about 40 ft.

Goniolithon myriocarpon Foslie 

Plate 275, figure 6

Goniolithon myriocarpon Foslie, 1904, Wiss. Meers., N. F. B. 7,

abt. Helgoland, Heft 1, p. 23. 

Weber van Bosse and Foslie, 1904, /Siftof/a-Expeditie Mon.

61, p. 45, pi. 9, fig. 6. 

Foslie, 1909, K. norske vidensk. selsk. Skr., no. 2, p. 9.

Description.—Thallus a thin crust. Hypothallus 

thin, poorly coaxial, or curved rows of cells. Cells 16/x20/x, long, 12/t-16/A wide. Perithallus moderately to well 

developed, cells 9/1-15/x, long, 9/x-ll/x wide. Megacells 

abundant in most area of perithallic tissue; 26/x-29/x 

high and 16/1-21/x, wide. No conceptacles present.

Remarks.—In growth habit and cell dimensions the 

Eniwetok specimens agree with Foslie's descriptions of 

this widely distributed Recent species.

Age: Recent and Miocene.

Locality: F-l, Eniwetok 1,232-1,248 ft (core).

Figured specimen: F-l-3-3 (1), USNM 40820.

Goniolithon fosliei (Heydrich) Foslie 

Plate 275, figure 7

Lithothamnion fosliei Heydrich, 1897, Deutsche, bot. Gesell.,

Ber. p. 15, 58. 

Lithophyllum fosliei Heydrich, 1897, Deutsche bot. Gesell.,

Ber. p. 15, 140.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 933

Goniolithon fosliei (Heydrich) Foslie, Weber van Bosse and 

and Foslie, 1904, Sfiftogra-Expeditie, Mon. 61, p. 46-48, pi. 

9, figs. 1-5.

Foslie and Printz, 1929, K. norske vldensk. selsk. Museet, 

Mon., p. 29, pi. 46, figs. 1-5.

Description.—Thallus a crust; superimposed thalli 

may form crustose masses over a centimeter thick. 

Thallus consists of well-developed coaxial hypothallus 

overlain by a perithallus that may be slightly or strongly developed. Hypothallic cells 20/A-38/* by 7//,-ll/*; 

perithallic cells 12//.-20//, by 8//.-10//,. Megacells rare in 

some specimens, fairly abundant in others, commonly 

3 to 5 in a vertical row. Conceptacles wide and low, 

800/i-l,000//, in diameter.

Remarks.—This Recent species widely distributed 

over Indian Ocean and tropical Pacific. According to 

Foslie (1904) and Lignac-Grutterink (1943, p. 291), 

there is considerable range in cell dimensions in both 

same and in different specimens. Foslie, working only 

with Eecent specimens, placed species in genus G-oniolithon. Lignac-Grutterink, working with fossil material, considered it as a typical Lithophyllum.

A number of infertile fragments attributed to this 

species were observed in slides from the Funafuti cores.

Age: Recent and Pleistocene(?). 

Locality: Funafuti, depth 526 ft. 

Figured specimen: British Museum slide 665.

Genus POROLITHON Foslie

Description.—Porolithon resembles LitJiopJiyllum in 

the structures of the hypothallus, perithallus, and conceptacles. It differs in having lenses of megacells in 

the perithallic tissue. These cells are much larger and 

commonly are more regularly arranged than the normal perithallic cells. A feature common to the genus 

is the presence of lateral pores connecting adjoining 

cells.

The genus contains both crustose and branching 

species. It occurs abundantly today in the tropical 

Pacific on and around the reefs. It is represented by 

a relatively small number of widely distributed species.

Members of this genus appear to develop most abundantly in relatively shallow well-circulated water. 

They are the most important builders of the algal ridge 

along the seaward margin of many reefs where their 

greatest development is from tide level down to 40 or 

50 feet.

The genus is young, geologically. So far no specimens older than Pliocene have been found. Porolithon 

did not become abundant until the middle of the 

Pleistocene.

For convenience in classification the species are 

grouped into three divisions based on growth habit.

The following table shows the dimensions and distribution of the species studied.

Measurements (in microns) and distribution of species of Porolithon

Species

Hypothallus 

cells

Length Width

Perithallus cells

Length Width

Conceptacles

Diameter Height

Megacells

Diameter Height Number 

in cluster

Locality Depth (feet) Age

Division 1.—Crusts

rich) Foslie.

6-12(20) 7-12 125-175 60-78 8-17 17-34 5-10

.-...do..........

En-1, 30-50.—

E-l, 10-30..—

535 and 726.. ..

Pleistocene (?). 

Do.

Do.

Division 2.—Large thick masses

(Foslie) Foslie.

9-14 9-11 200-270 100-125 13-18 20-30 7-12

.....do— ........

70, 110.—- — -

tocene(?). 

Do.

Do.

Division 3.—Strongly branching forms

(Foslie) Foslie.

marshallense Taylor...

9-13

14-23

9-30

9-14

12-18

8-9

10-14(20)

9-13

10-11

8-11

135-216

135-144

79—1 OS

81-90

10-18

n-is

28-35

25-45

7-9

4-6

8-12 Eniwetok E-l__-

En-6, 35; E-l,

50-60. 

10-30, 547-555

10-80, 30-35, 

60-70.

cene(?).

Pleistocene(?). 

Recent.
934 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Division 1—Crusts 

Porolithon onkodes (Heydrich) Foslie

Lithothamnion onkodes Heydrich, 1897, Deutsche bot. Gesell.

Ber., v. 15, p. 410. 

Porolithon onkodes (Heydrich) Foslie. Taylor, 1950, Mich.

Univ. Studies, Sei. ser., v. 18, p. 125, pis. 9, 61-63. 

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p.

232-233, pi. 55, figs. 6, 7; pi. 59, fig. 6.

Description.—Plant encrusting. Hypothallus thin, 

consisting of few layers of horizontally elongated cells. 

Perithallus tissue composed of rectangular cells 6/^-12/4 

(20/j,) by 7JU.-12/X arranged in vertical rows and poorly 

defined horizontal layers. Lenses of megacells occur 

at irregular intervals in perithallic tissue. In section 

they occur in clusters, commonly of 5 to 10. Megacells l7ju,-34/j, long, 8/^-17/x wide. Conceptacle chambers 125//.-175/A in diameter, 60/j,—78/x high.

Remarks.—Fairly abundant in some near-surface 

samples. Specimens correspond with Recent material 

collected at Bikini Atoll.

Age: Recent and Pleistocene(?).

Locality: Eniwetok, Engebi Island, En-1, 30-50 ft; Parry 

Island E-l, depth 10-30 ft. Funafuti, main boring. 535 and 

726 ft.

Division 2—Large thick masses 

Porolithon craspedium (Foslie) Foslie

Lithophyllum craspedium Foslie, 1900, K. norske vidensk. selsk.

Skr., no. 5, p. 26, 27.

Porolithon craspedium (Foslie) Foslie. Taylor, 1950, Mich.

Univ. Studies, Sci. ser., v. 18, p. 126-128, pis. 64-65.

Johnson, 1954, U.S. Geol. Survey Prof. Paper 260-M, p.

541, pi. 193.

Johnson, 1957, U.S. Geol. Survey Prof. Paper 280-E, p. 

232, pi. 56, figs. 4, 5 ; pi. 59, figs. 1-3.

Description.—Plant forms dense cushion-shaped 

masses with knobby or coarse fingerlike protuberances. 

Medullary hypothallus and marginal perithallus not 

sharply defined. Cells in rows and fairly distinct 

layers; perithallic cells 9ju-14//, by 9/x-ll>. Lenses of 

megacells abundant, which show a great range in size; 

the more conspicuous measure 20/^-30/j, high, 13/A-lS/j, 

wide; commonly they are in clusters of 7 to 12. Conceptacle chambers 200/^-270^ in diameter, 100^-125^ 

high.

Remarks.—A number of fragments were observed, 

all of which closely resemble Recent material collected 

at Bikini Atoll. Recent species grows in and just below the surf zone—particularly on lee side of reefs.

Age: Recent and Pleistocene(?).

Locality: Eniwetok K-l, depths 70-110 ft; Engebi Island, 

slides K-l-2 (2), K-l-2 (1) ; Funafuti, depth 40-70 ft.

Division 3—Strongly branching forms 

Porolithon aequinoctiale (Foslie) Foslie

Plate 275, figures 1, 2 

Lithophyllum aequinoctiale Foslie, 1909, K. norske vidensk.

selsk. Skr., no. 2, p. 46. 

Porolithon aequinoctiale (Foslie) Foslie. Taylor, 1950, Mich.

Univ. Studies, Sci. ser., v. 18, p. 132, pis. 68, 70.

Description.—Plants form masses of short wide 

branches. Eniwetok material consists of worn fragments mainly of perithallic tissue; perithallic cells 12ju,- 

18ju, by 9ju,-13ju,. Lenses of megacells abundant, showing as horizontal rows in section, commonly 7 to 9 in 

a row, but there may be many more. Megacells 27//,- 

high and llju,-18ju, wide. Conceptacle chambers 

16^ in diameter, 72^-108^ high.

Remarks.—Eniwetok fragments attributed to this 

species largely on basis of abundance and size of megacells and size of conceptacle chambers. Perithallic cells 

fall within size range but average a little wider.

Species grows in shallow water on outer-reef platform and in lagoons.

Age: Recent and Pleistocene ( ?).

Locality: Eniwetok E-l, depth 50-60 ft. (cuttings) and En6, 35 ft.

Figured specimens: En-6-29-2, USNM 40818; En-6-29-1, 

40817.

Porolithon gardineri (Foslie) Foslie

Lithophyllum gardineri Foslie, 1907, K. norske vidensk. selsk.

Skr., no. 8, p. 30. 

Foslie, 1907, Linnean Soc. London Trans., ser. 2, Zoology,

v. 12, pt. 2, p. 190. 

Lithophyllum (Porolithon) gardineri Foslie, 1909, K. norske

vidensk. selsk. Skr., no. 2, p. 44^5. 

Porolithon gardineri (Foslie) Foslie. Taylor, 1950, Mich. Univ.

Studies, Sci. ser., v. 18, p. 129-131, pis. 5-9; pi. 70, fig. 1;

pis. 71-73; pi. 76, fig. 2, pi. 77.

Description.—Plants cushion shaped, as much as 30 

cm in diameter and 20 cm high. Basal part crustose 

with long branches forming densely packed rounded 

heads. In section, heads show a regularly arranged 

medullary hypothallus with cells 9ju,-30;u, long, 9/x-13;u, 

wide. Marginal perithallus moderately thick, rather 

loose texture, cells 8ju.-19//, long and 9ju,-llju, wide, arranged in radial rows but not in distinct layers. Megacells abundant in perithallic tissue, in clusters of 8 to 

more than 20, commonly 4 to 6 in a section. They 

measure 28ju,-35ju, high and 9;u,-18ju, wide. Conceptacles 

110ju,-152/x in diameter and 68ju,-110ju, high.

Remarks.—This Recent species is one of common 

forms in the algal ridge of many atolls. It was observed in a number of slides from Funafuti drilling.

Age: Recent and Pleistocene ( ?).

Locality: Recent species widespread in Red Sea, Indian 

Ocean, and tropical Pacific. Fossil material observed in Funafuti core at depths of 10-30 ft. and 547-555 ft.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 935

Porolithon marshallense Taylor 

Plate 275, figures 3, 4

Porolithon marshallense Taylor, 1950, Mien, Univ. Studies Sci.

ser., v. 18, p. 128-129, pis. 67 and 76.

Johnson, 1954, U.S. Geol. Survey Prof. Paper 260-M, p. 542, 

pi. 197, fig. 1.

Description.—Plant compact mass of branches, each 

consisting of wide medullary hypothallus surrounded 

by relatively narrow marginal perithallus. Cells of 

hypothallus M/x-^S^ by 9^-14,0,, commonly about 16ju, 

by 10,*. Perithallic cells lO/i-lfy (20^) by fy-11/*, 

commonly about 12//, by 10//,. Megacells commonly 8 

to 12 in cluster, size 25^-45/x by ll/A-lS^, average 36//, 

by IS/*. Conceptacles 135/A-144//, in diameter, 81^-90^ 

high.

Remarks.—This species closely fits Taylor's description in cell size and in having cells arranged in distinct 

layers. Few conceptacle chambers observed, somewhat 

smaller than in type material. It differs from P. 

gardineri in having larger megacells, and in having distinct layers of cells. Recent species frequently grow in 

surf zone, slightly behind outer edge of reefs.

Age: Recent.

Locality: Eniwetok E-1, depths 30-35 and 60-70 ft (cuttings). 

Figured, specimens: E-1 60-70 USNM 40-819; E-l-30-35, 

USNM 40940.

Genus PARAPOROLITHON Johnson, 1957

The hypothallus and conceptacles are of the Lithophyllum type. The distinctive feature is that the perithallic tissue not only contains small lenticular clusters 

of large megacells such as characterize the genus 

Porolithon, but it also contains numerous smaller megacells which occur singly or in vertical groups as in 

Goniolithon. This genus is known only from the Miocene.

Paraporolithon saipanense Johnson

Paraporolithon saipanense Johnson, 1957, U.S. Geol. Survey 

Prof. Paper 280-E, p. 233, pi. 52, figs. 4, 5.

Description.—Thallus a warty crust 0.8-1.4 mm 

thick. Hypothallus poorly coaxial 75/*-225/* thick, 

composed of rectangular cells 12^-25/A long and ll//,- 

15/x, wide, averaging 13^, by lip. Perithallus of fairly 

regular rows of cells 13/4-17/* by 11/^-15^. Partitions 

between cell rows clearly developed; lenses of large 

megacells sparingly distributed through tissue. Sections through these show 4 to 8 cells to a cluster, averaging 5; megacells measure 46^,-68^ high and 15/*-18//, 

wide. Smaller megacells, 15/^-18^ by 14/*-18/* scattered 

abundantly throughout tissue, singly or in pairs. No 

conceptacles present.

Remarks.—Only one fragment of this species was 

observed in the Kita-Daito-Jima slides. In appearance

and cell measurements it agrees with the specimen described from Saipan.

Age: Miocene.

Locality: Kita-Daito-Jima core, depth 646 ft (197 m).

Specimen: Tohoku Univerity colln., slide 876.

Genus LITHOPORELLA Foslie, 1909

Weber van Bosse, A., and Foslie, M. H., 1904. The Corallinaceae of the Siboga Expedition. Mon. 61, 110 pp., 16 pis. 

Foslie, M. H.. 1909. Algologiske Notiser VI. K. norske vidensk.

selsk. Skr., no. 2, p. 1-63. 

Lemoine, Mme. Paul, 1917. In F. Borgesen. Rhodophyta of

the Danish West Indies. Dansk. Bot. Ark., v. 3, no. 1,

p. 147-200. 

Howe, M. A., 1919. Tertiary calcareous algae from the islands

of St. Bartholomew, Antigua, and Angiulla. Carnegie

Inst. Washington Pub. 291, p. 9-20, pis. 1-6. 

Setchell, W. A., 1943. Mastorphora and the Mastophoreae:

Genus and subfamily of Corallinaceae. Natl. Acad. Sci.

Proc. v. 29. no. 5, p. 127-135. 

Ishijima, W., 1954. Cenozoic coralline algae from the western

Pacific: Private publ., Tokyo, Japan, 87 p., 49 pis.

The identification of thin crustose coralline algae 

whose thalli are built of one or only a few layers of cells 

is extremely difficult and unless conceptacles are present, 

specific identification is impossible.

The term Lithoporella was used by Foslie in 1904 

(Weber van Bosse and Foslie, p. 73) as a subgenus under Mastophora, with Mastophora melobesioides Foslie 

as its type. Later Foslie (1909, p. 59) raised Lithoporella to full generic rank. This was accepted by 

American geologists without question for about 10 

years. Marshall A. Howe in 1919 (p. 17) states, "Foslie's establishment of a genus Lithoporella to receive the 

monostromatic calcified forms that he had previously 

referred to Mastophora seems justified." However, a 

year or two earlier, Mme. Lemoine (1917, p. 174), apparently as a result of studies of modern algae from 

the West Indies, preferred to consider Lithoporella a 

subgenus under Melobesia. In recent years, American 

geologists have tended to follow Howe's example and 

consider Lithoporella as an independent genus, while 

most European geologists and botanists have followed 

Mme. Lemoine.

Lithoporella has very thin monostromatic crustose 

thalli except around the conceptacles. The cells are 

rectangular, vertically elongated, and form a palisadelike layer. Rhizoids are absent. The thalli commonly 

grow superimposed or alternating with other crustose 

algae or encrusting Foraminifera to form thick crusts. 

Conceptacles are large, with a single aperture.

Lithoporella closely resembles Mastophora Decaisne, 

but Mastophora has long rhizoids for attachment, and 

normally the thalli do not grow superimposed. Another closely related genus is Heteroderma Foslie which
936 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

differs from Lithoporella in consisting of 1 or 2 layers 

of isodiametric cells which are not vertically elongated 

to form palisadelike layers. Adjacent thalli become 

confluent but never superimposed. Melobesia Lamouroux differs from Lithoporella by having horizontally 

elongated cells in the basal layer; the thallus may be 

several layers thick, and the conceptacles have a number of openings. 

Lithoporella ranges from Eocene to Recent. In existing seas it is abundantly represented by a few widespread species. They grow on almost any sort of hard 

object and have been found attached to noncalcareous 

algae. They live from tide level to at least 50 meters. 

A number of Recent and fossil species have been named. 

All show a wide range of cell sizes, even in a single 

specimen.

The following table shows the measurements and 

distribution of species studied.

Measurements (in microns) and distribution of species of Lithoporella

Species

Lithoporella melobesioides (Foslie) Foslie

cf. L. crassa IsMjima __ ... __ . .... __ _

longicella, Johnson n. sp._-_.. . _ _ ........

antiquitas Johnson n. sp

sp. A ____ ____________ . . _ .

sp. B ...

sp. C...._. .........

Cell dimensions

Length

25-76

34-45 

45-104 

30-60 

83-94 

23-46 

28-48

Width

13-23

11-15 

9-15 

13-22 

43-59 

16-23 

20-31

Conceptacles

Diameter

250-585

175-250

Height

38-158

95-115

Locality

Funafuti, Recent reef cores. .

Eniwetok, K-l__ _______

Eniwetok, E-l __ _____

Eniwetok, F-l_. ...----..---

Depth (feet)

75-1,000 

0-333

350 

260-270 

2, 003-2, 028 

2,675 

1, 718-1, 740 

380

Age

Pleistocene or Recent. 

Pleistocene. 

Eocene to Recent. 

Recent or Pleistocene (?). 

Pleistocene (?). 

Miocene. 

Lower Miocene. 

Upper Miocene. 

Pliocene-Pleistocene.

Lithoporella melobesioides (Foslie) Foslie

Mastophora melobesioides Foslie, 1903, K. norske vidensk. selsk.

Aarsber. 1902.

Mastophora (LithoporeHa) melobesioides Foslie. Weber van 

Bosse and Foslie, 1904, /Si&o^a-Expeditie Mon. 61, p. 73- 

75, figs. 30-32. 

Foslie, 1908, Alg. Nat. 5, K. norske vidensk, selsk, Skr.,

no. 7, p. 19.

Lithoporella melobesioides (Foslie) Foslie. Foslie, 1909, Alg. 

Nat. 6, norske vidensk. selsk. Skr., 1909, no. 2, p. 58, 59. 

Howe, 1918, U.S. Natl. Mus. Bull 103, p. 11. 

Howe, 1919, Carnegie Inst. Washington Pub 291, p. 16-19,

pi. 6. 

Mastophora melobesioides Foslie. Pfender, 1926, Soc. espanola

historia nat. Bol., v. 26, p. 327-328, pi. 15. 

Melobesia (Lithoporella) melobesioides Foslie. Lemoine, 1928

(a). Mus. nat. histoire nat., Bull. 1927, p. 550. 

Lemoine, 1928 (b). Inst. Catalonia Hist. Nat. Bull., ser. 2,

v. 8, no. 5-6, p. 104. 

Airoldi, 1931. R. Ace. del Lincee, Rend. v. 13, 5-6, 5 ann. 1,

pt. 6-7, p. 533-34. 

Airoldi, 1932. Paleontographica Italica, v. 33, p. 81, pi.

12, fig. 5. 

Miranda, 1935. Soc. espanola historia nat. Bol. v. 30, p.

285. 

Lemoine, 1938. Soc. G6ol. France, Compte rendu, pt. 7, p.

123 (Apr. 4, 1938). 

Lemoine, 1939. Mat. Carte Geol. de 1'Algerie, Mem. 9, p.

108-110, fig. 79.

Conti, 1943. Palaeontographia Italica, v. 41, p. 60. 

Lithoporella melobesioides (Foslie) Foslie. Lignac-Gruttirink, 

1943. Geol.-mijnb. genootsch. Nederland en Kolonien 

Verh., Geol. ser., v. 113, p. 292, pi. 2, fig. 8. 

Lithoporella (Melobesia) melobesioides (Foslie) Foslie. Johnson and Ferris, 1949, Jour. Paleontology, v. 23, no. 2, p. 

196, pi. 39, figs. 1-2.

Lithoporella melobesioides (Foslie) Foslie. Johnson and Ferris, 1950, B. P. Bishop Mus. Bull. 201, p. 18, pi. 8, fig. A.

Melobesia (Lithoporella) melobesioides Foslie. Conti, 1950.

Pub. Inst. Geol., Univ. Genoa Quad. 4, p. 130. 

Mastrorilli, 1950. Atti. Inst. Geol. Univ. Pavia, v. 4, p.

65-66. 

Lithoporella melobesioides (Foslie) Foslie. Johnson and Tafur,

1952. Jour. Paleontology, v. 26, no. 4, p. 541-542, pi. 62,

fig. 2, pi. 64, fig. 1. 

Ishijima, 1954. Cenozoic coralline algae from the western

Pacific, p. 47-18, pi. 45, figs. 1-6, pi. 46, fig. 1. 

Johnson, 1954. U.S. Geol. Survey Prof. Paper 260-M, p.

542-543, pi. 197, figs. 2-3. 

Johnson, 1957. USGS Prof. Paper 280-E, p. 234, pi. 37,

fig. 5, pi. 43, figs. 1, 2, pi. 49, fig. 4, pi. 56, fig. 6.

Description.—Thallus thin irregular crusts that consist of single layer of large vertically elongated rectangular cells; around conceptacles few additional layers of small cells may develop. Cell walls thick, showing great range in size even in same plant. Cells measure 25/J-76/* long and 13/*-23/x, wide. Conceptacle 

chambers 250/A-485/*, in diameter and 38/X.-158/* in 

height.

Remarks.—Fossils attributed to this species were 

found abundantly in all material studied from Funafuti, Kita-Daito-Jima, and Eniwetok.

Age: Eocene to Recent.

Lithoporella cf. L. crassa Ishijima 

Plate 276, figure 6

Lithoporella crassa Ishijima, 1945, Cenozoic coralline algae 

western Pacific, p. 50, pi. 48, figs. 1-3; pi. 49, figs. 1-3.

Description.—Thallus a single layer of vertically 

elongated cells in palisadelike rows; cells 34/X.-45/X, high 

and ll/x,-15/>i wide with thick walls. Numerous thalli
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 937

grow superimposed to form thick crusts. No conceptacles observed.

Remarks.—Represented by several infertile fragments. These closely resemble the material recently described by Ishijima from the Pleistocene of Formosa. 

In section they suggest Litfiophyllum megacrustum 

Johnson and Ferris (1950) from the Pleistocene of 

Fiji but differ in the more irregular arrangement of 

the cell layers, which are interpreted as individual 

thalli. Without a knowledge of the conceptacles it 

seems wise only to indicate their resemblance to Lithoporella crassa.

Age: Recent or Pleistocene(?).

Locality: Eniwetok hole K-l, depth about 350 ft (cuttings).

Figured specimen: K-l-30-1, USNM 40821.

Lithoporella longicella Johnson, n. sp. 

Plate 276, figures 3, 4

Description.—Thallus a single layer of long narrow 

palisade cells, which show a considerable range in size 

in a single thallus. Thalli may be irregular; numerous 

thalli growing superimposed to form thick nodular 

masses. Cells measure 45/A-104iu high and 9/x,-l'5/x wide 

(commonly 70/u by 12/u). Cell walls distinct but not as 

thick as many species of the genus. Conceptacles unknown.

Remarks.—This species is closely related to Ishijima's 

species L. australis and L. crassa but has longer cells 

with thinner cell walls and in being strictly monostromatic.

Age: Recent or Pleistocene(?).

Locality: Eniwetok E-l, depth 260-270 ft (cuttings).

Figured specimen: Holotype, USNM 40822.

Lithoporella antiquitas Johnson, n. sp. 

Plate 276, figures 1, 2

Description.—Thallus a single layer of vertically 

elongated cells SO/i-GO/A long and 13/x-22^ (28/*) wide. 

Conceptacles small, 175^ by 95^, to 250^ by 115/x. One 

shows an aperture with a neck about 40/x wide and 

260/4 long.

Remarks.—Cell size of this species within great size 

range of LitJioporella melobesioides, but below average 

size. Conceptacles of L. melobesioides measure 600/x1,000^, in diameter, those of L. antiquitas smaller. Because type slide of L. antiquitas shows aperture clearly, 

including exit tube, without doubt it cuts conceptacle 

across center and shows maximum diameter.

Age: Miocene.

Locality: Eniwetok E-l, depth 2,003 and 2,028 ft (cores).

Figured specimen: E-l-l-4(l) large. Holotype USNM 40825.

Lithoporella sp. A 

Plate 277, figure 14

Description.—Several fragments of LitJioporella in 

Miocene section showed large cells measuring 83/>i-94/i 

by 43iu,-59iu,. These cells larger and much wider than 

most members of genus and probably represent an undescribed species; without knowledge of conceptacles 

it does not seem wise to name it.

Age: Miocene.

Locality: Eniwetok hole F-l, depth 2,675 ft (core).

Figured specimen: F-l-6-25 (2), USNM 40823.

Lithoporella sp. B 

Plate 276, figure 5

Description.—Thallus a single layer of vertically 

elongated rectangular cells 23/x-46/x high and 16^-23/x 

wide. Conceptacles unknown.

Remarks.—Represented by several infertile specimens.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,718-1,740 ft (core). 

Figured specimens: F-l-4-10 (2) and F-l-4-20, USNM 

40824.

Lithoporella sp. C

Description.—Thallus monostromatic except around 

conceptacles. Cells elongated, often obliquely. Cells 

shown an appreciable range in size, as indicated below. 

Conceptacles unknown.

Cell

Slide dimensions 

No. (microns) Conceptacles Age

661(1) 32-44 by 20-31 Absent___ Pliocene-Pleistocene

661(2) 28-34 by 25-28 __do___ Do.

661(2) 34-48 by 22-24 __do___ Do.

Remarks.—If the ratio of cell width and length is a 

basis for species differentiation in this genus, then this 

material belongs to different species than preceding 

ones. However it does not seem wise to give it a name 

without knowledge of conceptacles.

Locality: Kita-Daito-Jima core, depth 115 m (380 ft).

Age: Pliocene-Pleistocene.

Specimen: Tohoku University colln., slide 661.

Genus DERMATOLITHON Foslie, 1899 

Algae in this genus develop small thin crusts characterized by a hypothallus formed of a single layer of 

large, obliquely elongated cells that may be contorted. 

The perithallus is formed of several to many layers of 

rectangular cells. The conceptacles are hemispherical 

to conical with a single aperture.

The genus is widely distributed today in tropical and 

temperate waters. The numerous species are commonly 

epiphytic but may grow, attached to shells, pebbles, and 

other objects. They are characteristic of the littoral
938 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

zone, commonly just below low tide level but reaching 

to depths of as much as 80 meters.

Dermatolithon marshallensum Johnson, n. sp. 

Plate 277, figure 13

Description.—Thallus normally monostromatic, consisting of single hypothallic layer. Cells obliquely 

elongated, measuring 40ju,-63ju, high and 18^-27^ wide. 

Conceptacle hemispheric, SOOju, in diameter and 125/* 

high.

Remarks.—D. m,arshaUensum differs from D. saipanensum Johnson from the Miocene of Saipan in having 

shorter hypothallic cells, smaller conceptacles, and in 

lacking the well-developed perithallus found in D. 

saipanensum. It differs from the widely distributed 

Recent species D. papUlosum (Zanardini) Foslie in 

having wider hypothallic cells and developing more 

regular thallus.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,725-1,985 ft (cores).

Figured specimen: F-l-5-lS(3). Holotype USNM 40826.

Subfamily CORALLINOIDEAE (articulate corallines)

Fragments of articulate coralline algae were found 

in considerable numbers in the Eniwetok drill samples 

but were comparatively rare in the material from 

Funafuti and Kita-Daito-Jima. In a few instances 2 

or 3 segments were found connected by nodes but the 

majority of the fossils consist of single segments. The 

identification of such fragments is difficult, if not impossible, because many living species have been discriminated by using such features as size and shape of the 

plant or its fronds, character of the branching, or other 

features that cannot be recognized in fragments. The 

size, shape, and position of the conceptacles have also 

been used in separating Recent species. Because conceptacles are normally external and seldom are calcified, they are of little use in identifying fossils.

Attempts have been made to use features that can 

be determined from segments. These include: (a) 

The size and shape of the segments, (b) the dimensions 

of the cells along the axis of the frond, (c) the number of rows of cells in a segment, and (d) the range in 

size of cells. The first feature-listed above is useful in 

separating genera but is of questionable value in separating species because in a number of Recent species, 

the segments from different parts of the plant are 

known to differ considerably in size and shape and in 

the number of cell rows that form the segments. Measurements of the length of the cells along the axis also 

show appreciable variation, but it may be that for a 

given species the cell dimensions will fall within certain limits and thus be useful in characterizing the

species. Such, indeed, is the case among the crustose 

corallines, but sufficient work has not yet been done 

with the articulate forms to decide the question. The 

author has, therefore, been reluctant to attach specific 

names to fossil articulates except where large numbers 

of specimens, including those showing joined segments, 

were available for study.

Representatives of three genera were found in the 

collections studied. Corallina and Amphiroa were the 

most abundant, with a few examples of Jania.

Genus JANTA Lamouroux, 1812

The plants consist of masses of slender dichotomously branching fronds arising from an inconspicuous 

disc. Each frond consists of a series of slender segments formed of tiers of hypothallic cells surrounded 

by a narrow perithallus, which is characteristically restricted to a single layer of small rectangular cells. 

The hypothallic cells tend to be wider in proportion to 

length than in most genera of articulate corallines. In 

many instances, they appear wedge shaped in section. 

Conceptacles usually occur singly in swollen terminal 

segments of branches.

Today this genus is widespread in the tropic and temperate seas where it is represented by many species. At 

least three species grow on the reefs at Eniwetok. The 

plants are fairly abundant locally on the undersides 

of rocks and in shallow pools on the reef flat. Fossil 

representatives are known from rocks as old as Late 

Cretaceous.

Jania miocenica Johnson n. sp.

Plate 278, figures 6, 7, 8

Description.—Slender segments with dimensions (in 

microns) as follows.

Slide

F -1-4-8(2).. _

F-l-4-10(2)____

F-l-5-18(3)_-_-

F-l-5-l(l)___-

Size 

segment

1.0X0.36

l.OX .25 

1.5X .3

I. IX .25 

1.7X .33 

1.3X .3

Number 

of cell 

rows in 

segment

20 

43 

17+ 

24 

31 

26+

Number 

of cells 

in a 

row

16-18 

18-21 

20 22 

18-22

16+ 

13

Cells

Medullary, 

length

38-47 

31-47 

41-47 

32-41 

41-47 

37-46

Hypothallus, 

width

13-15

12-16

16-19 

17-23 

16-23

Perithallie

Length

(0 

0) 

10-13

19-28

Width

0) 

C) 

11-16

21-28

1 Absent.

A conceptacle chamber is shown on one specimen; it 

measures approximately 350/i in length and 100/i in 

width (pi. 278, fig. 8).

Remarks.—Numerous fragments were observed. 

Specimen showing conceptacle chamber believed to be 

first of Miocene age to be found.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 939

Age: Miocene.

Locality: Eniwetok F-l, depth 1,718-1,980 ft (cores). 

Figured specimen: F-l-4-8 (2), holotype USNM 40919; 

F-l-4-10 (2), USNM 40918.

Jania vetus Johnson

Jania vetus Johnson, 1957. U.S. Geol. Survey Prof. Paper 

280-E, p. 237, pi. 52, fig. 2.

Remarks.—Several well-preserved segments belonging to this species found in one of Eniwetok cores. 

Age: Miocene. 

Locality: Eniwetok F-l, depth 1,232-1,248 ft (core).

Jania sp. A 

Plate 278, figure 4

Description.—Long regular cylindrical segments 

about 2.0 by 0.37 mm. Segment contains 28 to 30 tiers 

of cells, 17 to 21 cells to a row. Hypothallic cells 59//r73/x, long, 16/A-20/A wide. Marginal cells 23/A-28/* long, 

14/A-18/A wide.

Remarks.—Several well-preserved segments and 

pieces of segments found in the Eocene limestones of 

Eniwetok.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,320-4,340 ft (core).

Figured specimen: F-l-12-4(l) bottom, large, USNM 40916.

Genus AMPHIROA Lamouroux, 1812

Plants develop from a small basal disk. They consist of clusters of segmented fronds that branch dichotomously or trichotomously at regular intervals. 

Fronds formed of calcified segments alternating with 

uncalcified nodes. Segments cylindrical to flattened, in 

some cases having a thick midrib and thinner margins. 

Each segment contains a well-developed medullary hypothallus. In most Recent and Pleistocene species, the 

hypothallus is built of alternating tiers of long and 

short cells. Older species may have hypothalli with 

tiers of cells of equal or nearly equal length. The marginal perithallus is moderately well developed, built 

of layers of small rectangular cells. Conceptacles are 

lateral, more or less imbedded in the perithallic tissue, 

often projecting above the outer surface.

This genus occurs abundantly in the warm seas of 

today. Fossils are known from rocks as old as Late 

Cretaceous. A considerable number of fragments were 

observed in the Eniwetok material.

Amphiroa fortis Johnson, n. sp. 

Plate 277, figures 8, 9

Description.—Segments 0.9-4.0 mm long and 0.3-0.75 

mm wide. Cell rows of medullary hypothallus regularly arranged with tendency to alternation of length 

after the formula—3 long, 1 short. Cell lengths 63/A71/x, in the long rows, and 59^-63^ in the short rows.

Cell widths 6/A-ll/*. Marginal cells 15/A-21/A long and 

7/x-ll/A wide. No conceptacles observed.

Remarks.—This species abundantly represented in 

core F-l-11. Characterized by the regularity of its 

cell rows and the length of their cells.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,197-4,222 ft (core). 

Figured specimens: F-l-11-1, holotype USNM 40834; F-l11-7, paratype USNM 40835.

Amphiroa sp. A 

Plate 277, figure 6

Description.—Segments 1.8-2.5 mm long and 0.35- 

0.39 mm wide. Medullary hypothallus formed of layers of cells 54/A-81/* long and 11^-18^ wide. Cell layers 

tend to follow pattern of 2 layers of long cells alternating with 1 of short cells. Cells in long layers 58^-80/j. 

long, 11^-16^ wide. Cells in short layers 54^-65/A long, 

11^-14^ wide. Marginal cells missing. No conceptacles observed.

Remarks.—Represented by about a dozen specimens 

in slides from F-l-15. This species has unusually long 

slender segments. Unfortunately, all are badly worn. 

Without a knowledge of marginal cells and conceptacles it does not seem desirable to give a specific name.

Age: Late Eocene.

Locality: Eniwetok F-l, depth approximately 4,540-4,550 ft 

(core). 

Figured specimen: F-l-15-14, USNM 40945.

Amphiroa sp. B 

Plate 277, figure 7

Description.—Segments composed of central hypothallus with layers of cells alternating—1 long and 1 

short. Long cells 30^-48^ long, 8^-11/x wide; short 

cells 14ju,-18|U, long, 8^-llju, wide. No marginal cells or 

conceptacles present.

Remarks.—Represented by two small badly worn 

fragments but of interest because of the pronounced 

and regular alternation of length of cell layers. This 

feature, while characteristic of most Recent and 

Pleistocene members of the genus, appears to be much 

less well developed in older species and is seldom noticeable in the early Tertiary forms seen by the writer.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4500-4525 ft (core).

Figured specimen: F-l-14-8(2) large, USNM 40914.

Amphiroa medians Johnson n. sp. 

Plate 278, figures 1, 2, 3

Description.—Fronds consist of segments 1.2-1.6 mm 

long and 0.45-0.66 mm thick. Conceptacles unknown. 

Dimensional data in microns are given in the following 

table.

584500 O -61 -4
940 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Slide

^-1-5-1(11,). .................................................. ...........

F-l-b-K'i'L). .............................................................

F-1-5-2&)...................... ..........................................

Size of 

segment

1306X608 

1250X450 

1550X540

Number of 

cell rows in 

segment

20 

17+ 

31+

Number of 

cells in a 

row

27-31 

24-29 

37-40

Formula

2-2, 2-1

1-1, 2-1 1-1,2-1

Medullary hypothallus

Long cells

63-71X13-16 

66-76X14-16 

52-62X14-18

Short cells

53-63X 9-14 

63-65X 9-14 

47-55X13-17

Marginal 

perithallus

17-26 (34) X 12-25 

Worn off. 

Worn off.

Remarks.—A number of specimens found in core 

F-l-5. Cell dimensions and relatively slight difference 

in length between long and short cells appear to be most 

distinctive characteristics of this species.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,000 ft (core).

Figured, specimen: F-1-5(1L), holotype USNM 40923; F-l5(1L), USNM 40809; and F-l-5-l(4L), USNM 40915.

Amphiroa sp. C 

Plate 278, figure 5

Description.—Segments about five times as long as 

wide. Cell layers of central hypothallus of nearly 

equal length but show tendency for slightly longer cells 

to alternate with shorter cells. Detailed dimensions in 

microns are given in the following table.

Slide

F-l-5-1 (2)............. .................................................

F-l-5-3(l) ..-—--........-..........--——..........................

Size of 

segment

5.6X1.2

Number 

of cell 

rows in 

segment

34 

36

Number 

of cells in 

a row

16-22 

18-20

Formula

1-1 

1-1

Medullary hypothallus

Long cells

48-60X14-18 

48-58X10-16

Short cells

45-56X11-17 

40-55X10-15

Marginal 

perithallus

Absent 

14-22X14-18

Age: Miocene.

Locality: Eniwetok F-l, depth 1,797-2,003 ft (core).

Figured specimen: F-l-5-3(l) small, USNM 40917.

Genus CORALLINA Linnaeus, 1758

The plants have a calcified crustose base from which 

arise numerous erect fronds that generally branch in 

a plane. The branching is commonly pinnate. The 

calcified segments are cylindrical or flattened, consisting of a medullary hypothallus surrounded by a thin 

cortical layer (perithallus). The medullary hypothallus consists of long narrow cells in layers of equal 

length. Nodes between the segments are normally not 

calcified. They are formed of a single layer of very 

long cells. Conceptacles are ovoid, terminal on short 

branches.

Corallina segments occur in considerable quantities 

at a number of levels in the Eniwetok drill holes. 

They represent a number of different species, several 

of which are described. Much of the material is too 

worn and frayed to permit specific identification.

Segments of articulate corallines attributed to this 

genus were observed in the loose and poorly consolidated material in the upper 70 feet of the main boring 

at Funafuti and in the upper 40 feet of the second boring. The material was not identified specifically.

Corallina prisca Johnson

Corallina prisca Johnson, 1957, U.S. Geol. Survey Prof. Paper 

280-E, p. 239-240, pi. 37, fig. 4, pi. 40, fig. 10, pi. 44, figs. 

1, 2, 7-11.

Description.—Segments flattened to nearly cylindrical. Cells of medullary hypothallus in center of tiers 

68/A-104/* long, 7/*-10/* wide. Perithallic cells 16/*-21/* 

long, 9ju-llju wide. No conceptacles observed.

Remarks.—A number of fragments were observed in 

slides of the Eniwetok cores which in appearance and 

dimensions correspond to this species described from 

the Eocene of Saipan.

Age: Late Eocene.

Locality: Eniwetok F-l, depth 4,500-4,550 ft (core).

Corallina eniwetokensis Johnson n. sp. 

Plate 277, figures 10, 11, 12

Description.—Fronds composed of short slender segments, 0.5-0.8 mm long and 0.17-0.29 mm wide with 

rather small nodes. Cells of medullary hypothallus 

62ju-120ju long and 8/A-12/* wide. Marginal cells 20^-39^ 

by 13ju-24/A. Conceptacles unknown. Detailed dimensions (in microns) are given in the following table.

Slide

F-l-3-10(4L) ......... ........

F-1-3-10C3L). .......... ........ ..

F-l-3-10(3L) ..................

F-l-3-10(4L)__... ........ ..

Size of segment

Length

640 

596 

695 

654 

701 

687 

680 

598 

536

Width

290 

252 

319 

194 

220 

173 

267 

246 

352

Size of node

Length

175 

103 

116

102

101

100

Width

187 

179 

146

147

217

210

Node cells

Length

24 

39 

?

?

7

Width

10-13 

10-11 9-11

8-10

?

Hypothallic cells

Length

70-110 

62-120 

90-113 

97-110? 

82-110 

87-112 

98-123 

90-120 

90-108

Width

8-10 

8-10 

8-10 

9-12 

9-11 

9-11 

10-12 9-12

Perithallic cells

Length

31 

20-27 

27 

25-39 

28-30 

24-27

15^21

Width

13-19 

13-20 

13 

14-24 

12-18 

13-18

10-15

Number of 

cells in 

row

18-20 

18 

14-15 

14-16 

13-14 

13 

20-22 

19-21 

18-21

Number of 

cell rows 

in segment

6 

6 

8

7 

7 

6 

5 

5 

5
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 941

Remarks.—In general appearance this suggests 

Corallina neuschelorum Johnson but differs in having 

more slender fronds and larger cells.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,230-1,248 ft (core). 

Figured specimens: F-l-3-10(4) large, holotype, USNM 

40828; F-l-3-lO(3) large, paratype, USNM 40827.

Corallina neuschelorum Johnson

Corallina neuschelorum Johnson, 1957, U.S. Geol. Survey Prof. 

Paper 280-E, p. 239, pi. 37, fig. 3, pi. 50, figs. 1-4.

Description.—Small delicate species; fronds formed 

of many short segments. Hypothallic cells 65ju,-105ju, 

long, 7ju-10/x wide. Marginal cells 10/x-15ju by 9/x-ll//,. 

Numerous measurements and illustrations given in 

original description.

Remarks.—Eniwetok specimens appear to be identical with species as described from the Miocene of 

Saipan. They occur abundantly in the F-l-5 core.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 ft (core).

Corallina marshallensis Johnson, n. sp. 

Plate 277, figures 2, 3

Description.—Segments 0.8-1.2 mm long and 0.259- 

0.351 mm wide with 6 to 14 layers of cells. Top of 

layers flat or slightly depressed. Cells 99/x,-140ju long 

and 9/^-12^ wide. Marginal cells 15/x-27/x wide and 

9ju,-13/x high. Node 200/x,-250ju long. Conceptacles unknown.

Remarks.—This species has longer than average 

medullary cells and unusually wide marginal cells. 

Combination of cell dimensions differs considerably 

from that of any previously described Miocene species.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,978-2,003 ft (core).

Figured specimens: F-l-5-33(2), holotype USNM 40829; 

USNM 40830.

Corallina sp. A 

Plate 277, figure 5

Description.—Segments about 0.75 mm long and 

0.25 mm wide. Nodes 0.08-0.09 mm long and 0.25 mm 

wide. Medullary hypothallic cells attain lengths of 

115ju,-126ju and widths of 9ju-14/x. Marginal cells 20ju21ju by 13ju,-16ju. No conceptacles observed.

Remarks.—Represented by a number of worn pieces. 

Species is close to C. otsukiensis Ishijima in cell dimensions.

Miocene.

Locality: Eniwetok F-l, depth 1,232-1,240 ft (core). 

Figured specimen: F-l-3-3(2), USNM 40831.

Corallina sp. B 

Plate 277, figure 1

Description.—Frond consists of number of segments 

containing 8 to 10 layers of cells. Segments 750/x1,000/* long; cells 42^-64^ long, 8/*-ll/* wide; nodes 

110/A-140/A long. Conceptacles unknown.

Age: Miocene.

Locality: Eniwetok F-l, depth 1,718-1,740ft (core).

Figured specimen: H-6, USNM 40832.

Corallina sp. C 

Plate 277, figure 4

Description.—Segments cylindrical, 1.5-2.0 mm long 

and 0.3-0.4 mm in diameter with 16 to 18 gently arched 

layers of cells. Cells 63/^-81^ long, ll/*-13/* wide. Marginal cells 14/A-16/* long, 8/*r-10/* wide. Nodes and conceptacles unknown.

Remarks.—In shape of segments and general appearance this species suggests Corallina elliptica Ishijima 

but has considerably shorter and wider cells. Represented by a number of fragments near base of F-l-5 

core.

Age: Miocene.

Locality: Eniwetok F-l, depth 2,001-2,003 ft (core).

Figured specimen: F-l-5-40(5), USNM 40833.

CHLOROPHYTA (green algae)

Family DASYCLADACEAE 

Genus DACTYLOPORA Lamarck, 1816

Dactylopora? sp. 

Plate 278, figures 9-12 ; plate 279, figures 3, 4, 5

Description.—Horizontal segments 0.8-2.2 mm in 

diameter. Central stem 0.275-0.350 mm thick. Primary 

branches 26 to 28 in a whorl, with diameters of 40/*- 

50/*. No sporangia observed.

Remarks.—Represented by worn and poorly preserved horizontal segments that belong in or close to 

Dactylopora Lamarck.

Age: Late Eocene.

Locality: Eniwetok E-l, depth 2,802-2,808 ft (core).

Figured specimens: E-l-2-9 (2) large, USNM 40920; E-l-2-9 

(3) large, USNM 40921; F-l, depth 2,805 ft, USNM 40942.

Genus ACICTTLARIA d'Archiac, 1943

Acicularia sp. 

Plate 279, figures 6, 7

Numerous fragments of perforated calcareous plates 

appear to represent a member of this genus. They are 

too fragmentary to permit specific identification but are
942 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

of interest as the first fossil representatives of this genus 

from, the Pacific area.

Age: Late Eocene.

Locality: Eniwetok E-l, depth 2,802-2,808 ft (core).

Figured specimen: E-l-2-9, USNM40944.

Dasycladaceae occurrences in cuttings from E-l, Eniwetok

Numerous specimens of Dasycladaceae were obtained 

from washed samples of well cuttings from Eniwetok 

hole E-l in the interval between 2,780 and 3,100 feet. 

A superficial examination of the specimens yielded the 

following data:

Depth (feet) Specimen 

2780-2790——__ Dasycladaceae, 

2830-2840——— Dasycladaceae, 

2850-2860——— Dasycladaceae,

tioning.

2890-2900.___ Dasycladaceae, 

2890-2900—__ Dasycladaceae, 

2900-2910——__ Dasycladaceae, 

2910-2920—__ Dasycladaceae, 

2930-2940——— Dasycladaceae, 

2950-2960——— Dasycladaceae,

polia, sp.

2960-2970-___ Dasycladaceae, 

2970-2980—__ Dasycladaceae, 

2980-2990___ Dasycladaceae, 

2990-3000___ Dasycladaceae, 

3000-3010___ Dasycladaceae, 

3030-3040___ Dasycladaceae, 

3050-3060-___ Dasycladaceae, 

3060-3070____ Dasycladaceae, 

3090-3100___ Dasycladaceae,

probably Cymopolial sp. 

probably Cymopolia 1! sp. 

genus uncertain without secLarvaria"! sp.

CymopoUa"! sp.

undet.

CymopoUa"! sp.

uncertain, possibly Larvaria.

several genera including CymoCymopoUal and another genus.

undet.

undet.

undet.

undet.

undet.

undet.

undet.

undet.

Family CODIACEAE

Genus EtALIMEDA Lamouroux, 1812

Plate 279, figures 1, 2; plate 280, figures 1-4

These plants are bushy tufts of segmented branching 

stems or fronds. The segments may be subcylindrical, 

flattened, conical, or broad and leaflike. The young 

growing segments are bright green and uncalcified. 

Calcification occurs with age. It begins at the outer 

surface and is extended inward; the entire segment 

may eventually be calcified but commonly the process 

is incomplete.

Recent species of Halimeda are separated largely on 

the basis of the growth habit of the plant, structure 

of the nodes, and size and shape of the segments (Barton, 1901, p. 1-4). Because the fossils consist of loose 

segments it is seldom possible to assign them to species 

although the generic features are easily recognized.

Halimeda segments were numerous in all the Funafuti drill samples and were an important constituent 

in the lagoon drill holes (Halligan, 1904). A few were 

recognized in the Kita-Daito-Jima hole from sediments 

thought to be of Pleistocene age. In the Eniwetok

drill holes, they were particularly abundant in the 

younger beds but segments were recovered from a core 

in hole F-l at a depth of 3,655-3,665 feet. Halimeda 

segments are so light and porous that they can travel 

almost indefinitely in heavy drilling mud. Some of 

the lowest occurrences from E-l listed below may have 

been derived from younger horizons.

Figured specimens: From Eniwetok, USNM 40941; Kita Daito 

Jima; Funafuti core.

Occurrences of HALIMEDA in cuttings from E-l, Eniwetok

Comments 

Abundant.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do. 

A few.

Do.

Do.

Do.

Do.

A few worn and broken

pieces.

A few worn fragments. 

A few segments. 

A few shreds. 

A few small segments.

Do.

A few fragments. 

A few small segments.

Do.

Do.

Do.

A few broken segments. 

A few small segments.

Do.

Do.

Microcodium sp.

Description.—Thallus spherical, globular, or forming an irregular crust. In section usually elliptical, 

circular, or fan shaped. Consists of a circular or elongated central part or nucleus surrounded by large 

elongated petallike growths of "palisade cells." These 

fan out from the central portion of the circular or oval 

masses. The encrusting forms have a greatly elongated nucleus, from the sides of which the palisade 

cells grow out roughly parallel to one another.

The structure of the central part or nucleus is not 

preserved. The palisade cells appear as blades of clear 

or nearly clear crystalline calcite.

Some typical dimensions (in microns) are tabulated 

as follows.

Depth, (feet) 

10-20 

30-35

30-35

30-40

30-40

50-60

60-70

60-70 

70-80

80-90

90-100

100-110

110-120

120-130

130-140 

200-210

290-300

340-350

380-390

400-410

450-460

460-470

480-490

520-530

530-540

950-960

970-980

990-1,000

1,100-1,110

1,160-1,170

1, 170-1, 190

Species 

Halimeda opuntia (Linnaeus) Lamouroux... 

__ do ______ . .........................

Halimeda opuntia f. triloba Barton ____ ..

....do....... .......... _ ..................

____do __________ ______ .....

Halimeda opuntia (Linnaeus) Lamouroux.—

__ do.. .............................

-.-do..-.-.-.....--—. .................

....do......................................

....do..... ———— — - — - — _ ———

Halimeda cf. opuntia (Linnaeus) Lamouroux. 

.—do... .————.———.____ — .........

——do... —— ....................... . ..

....do.... ..................................

—— do... — ..... ...........................

.... do.... ——-._.——————_ ..........

——do..—— ——..—————_——— ... ..

.... do.......... .................... ........

.—do......... .............................

..-do.——— .......... -——_———_ —— _. ——do.— ——— ———— .———————_

....do....... ........ .......................

..._do.— ——————————— —— ....do.—— ——._. — ——— —..._——— . —— do.. —— ..... ... ... ......... ... .... ....

....do ...... ...............................

Genus MICEOCODITTM Gliick

Slide

661

Entire plant

Shape

Rounded... _._-

_____do__. ______

Length

500 

485 

1160

Width

400 

410 

600

Nucleus

Length

142 

205 

330

Width

135 

112 

122

Palisade cells

Length

110-180 

115-185 

98-182

Width

35-65 

48-60 

35-62

Remarks.—Kita-Daito-Jima material agrees "with 

Gliick's (1912) original description from Miocene of
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 943

Germany. It is identical with specimens found in Miocene of Saipan. Similar material was also observed in 

upper Miocene of Eniwetok. A discussion of this problematical organism has been published by Johnson 

(1953, p. 84-86).

Miocene.

Locality: Kita-Daito-Jima cores, depth 380 ft (115-118 m) 

and 630 ft (189 m). Eniwetok F-l, depth 1,232-1,248 ft (core).

Specimens: Tohoku University colln., slides 661 and 821; 

Eniwetok F-l-3-3 and F-l-3-4.

GEOGRAPHIC DISTRIBUTION AND STRATIGRAPHIC 

OCCURRENCES OF ALGAE

The known geographical distribution and stratigraphic occurrences of species of algae described in the 

present report is given in the following tables.

Known geographical distribution

of the species of coralline algae 

described in this report

Recent and Pleistocene species

Archaeolithothamnium erythraeum (Roth.)

Foslie..— ...... .........

schmidti Foslie ._ ___ ... _

puntiense Airoldi _ . __ __ .. _ .

Ooniolithon fosliei (Heydr.) Foslie... .....

fr utescens Foslie ___ _ ..

myriocarpon Foslie. -.--.-.. __ ..

hanzaicae Johnson __ _ .

kotschyanum linger _ __ .... __ ....

okamurae Foslie-. _ .......... .

quadratumlshiiima. ------ __ .. . .

samoense Foslie ...

stefaninii Airoldi ..... _

Lithoporella cf. L. crassa Ishijima ...

longicella Johnson __ -.---..... ......

melobesioides (Foslie) Foslie.. ........

Lithothamnium aff. L. aucklandicum

Foslie........... . . .

cf. L. nitidum Foslie ................

fu nafutiense Foslie . . . . . __ __

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Q

X

X

X

X

X

X

1& 03 1-1

o

2o

n,•a

a

o

&

X

X

X

X

%

8

o

§

•§

M

X

X

X

T)

J•a

§

OQ

X

a

*-<

bo

<

g

n OQ

S £? £ "3

S-i M

Known geographical distribution 

of the species of coralline algae 

described in this report 

— Continued

Recent and Pleistocene species — Cont.

Miocene species

lauense Johnson & Ferrls.. _...-.. _

Eocene species

oulianovi Pfender _ ——— —————

Lithothamnium cf. L. abrardi Lemoine ....

Comllina nrisca Johnson...----.-------.-

Eniwetok

X

X

X

X

X

X

X

X

X 

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

Bikini

X

X

X

X

X

--

--

--

Funafuti

X

X

X

X

X

--

--

--

Kita-Daito-Jima

--

--

-

§ 

n '3 

OQ

X

X

X

X

X

X 

X

X

£ 

A

X

--

--

Dutch Indies East 

X

X

X

X

--

--

--

03

a

03

1-8

X

X

--

--

Pacific Tropical 

X

X

X

X

X

X

-

--

--

Indian Oce

X

X

X

X

--

--

--

Somaliland

-

X

X

.3 

1

3

-

X

X

X

X

X

a '3 

e. OQ

-

X

-

g 

!*

fe M

--"

X

----

Occurrences of algae in drill holes F-l and E-l

Depth (feet) 

0-45

Drill hole F-l

Porolithon sp. and Halimeda opuntia (Linnaeus) 

Lamouroux.

45-110 Porolithon? sp., Halimeda? sp_

110-190 

190-280

280-330 

330-625 

625-975

975-1, 045

Halimeda? sp., Lithothamnium? sp_ 

Halimeda sp.___________________

No determinable algae_. ______ ______________

Halimeda sp_________________________________

No algae recognized except fragments of Halimeda sp. 

No samples.

Depth (feet) Drill hole E-l

0-30 Porolithon onkodes (Heydrich) Foslie (10-30), 

Porolithon marshallensie Taylor (10), Halimeda 

opuntia (Linnaeus) Lamouroux.

30-90 Porolithon marshallense Taylor, Porolithon aequinoctiale (Foslie) Foslie (50-60), Halimeda 

opuntia (Linnaeus) Lamouroux, Halimeda 

gracilis Harvey.

90-145 Halimeda opuntia (Linnaeus) Lamouroux, Halimeda? sp.

145-300 Lithoporella longicella Johnson, n. sp. (260-270), 

Halimeda cf. H. opuntia (Linnaeus) Lamouroux. 

300-530 Halimeda sp. 

530-840 Halimeda sp. 

840-1, 190 Occasional segments of Halimeda sp.
944 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

Depth (feet) Drill hole F-l

1, 045-1, 060 No algae recognized.

1, 060-1, 080 No samples.

1, 080-1, 232 No algae recognized.-------------------------

1, 232-1, 248 Jania vetus Johnson, Corallina eniwetokensis Johnson, Corallina sp., A, Microcodium sp., Halimedaf sp.

1,248-1,718 No samples.

1, 718-1, 740 Archaeolithothamnium marshallensum Johnson, n. 

sp., Archaeolithothamnium cf. A. taiwanensis 

Ishijima, Lithothamnium Upturn Johnson and 

Ferris, Lithothamnium sp. C, Mesophyllum spp. 

A and B, Lithophyllum Madosum Johnson, Lithoporella sp. B, Jania miocenica Johnson, n. 

sp., Corallina sp. B.

1,740-1, 975 No samples-_-._______-_--_-_--_-_----------

1, 975-1, 978 Lithophyllum johnsoni Ishijima, Lithophyllum 

Madosum Johnson.

1. 978-2, 003 Archaeolithothamnium crustatum Johnson, n. sp., 

Archaeolithothamnium marshallensum Johnson, 

n. sp., Archaeolithothamnium eniwetokensis 

Johnson, n. sp., Lithothamnium cf. L. mirabile 

Conti, Lithothamnium sp. A, Mesophyllum cf. 

M. arakuraensis Ishijima, Mesophyllum eniwetokensum Johnson, n. sp., Mesophyllum japonicum Ishijima, Mesophyllum sp. A, Lithophyllum 

johnsoni Ishijima, Lithophyllum cf. L. prelichenoides Lemoine, Lithophyllum kladosum Johnson, Lithophyllum profundum Johnson, Lithoporella melobesioides (Foslie) Foslie, Jania 

mioceneium Johnson, n. sp., Amphiroa medians 

Johnson, n. sp., Amphiroa sp. C, Corallina 

neuschelorum Johnson, Corallina marshallensis 

Johnson, n. sp., Corallina sp. C.

2. 003-2, 130 No algae recognized-___-_-______---__--_--_-.-

2, 130-2,662 No samples----..------.--------------------

Depth (feet)

1, 190-1, 230 No 

1, 230-1, 715 No

Drill hole E-l

recognized, 

observed.

1, 715-1, 835 Archaeolithothamnium crustatum Johnson, n. sp. 

(1,718-1,740), Lithophyllum kladosum Johnson, 

Lithophyllum? sp., Lithoporella melobesioides 

(Foslie) Foslie.

1, 835-1, 993 Lithophyllum? sp., Lithoporella melobesioides 

(Foslie) Foslie.

1, 993-2, 003 Lithophyllum kladosum Johnson.

2, 662-2, 687 Archaeolithothamnium crustatum Johnson, n. sp., 

Archaeolithothamnium lauense Johnson and 

Ferris, Lithothamnium Upturn Johnson and 

Ferris, Lithothamnium sp. B, Lithothamnium 

sp. C, Mesophyllum cf. M. arakuraenis Ishijima, 

Mesophyllum cf. M. savornini Lemoine. Lithoporella sp. A, Lithoporella melobesioides (Foslie) 

Foslie.

2, 687-3, 052 No samples_________________________________

3, 052-3, 055 Mesophyllum robustum Johnson.__._______-__._

3,055-3,350 No samples. ________________________________

3, 350-3, 353 Lithophyllum? sp.

3, 353-3, 655 No samples.

3, 655-3, 665 Archaeolithothamnium oulianovi Pfender, Archaeolithothamnium nummuliticum (Giimbel) Rothpletz, Archaeolithothamnium cf. A. hemchandri 

Rao, Lithophyllum cf. L. lingusticum Airoldi, 

Lithoporella melobesioides (Foslie) Foslie, Halimeda sp. (molds).

2, 003-2, 028 Lithopyhllum Madosum Johnson, Lithothamnium 

sp. D, Lithoporella antiquitas Johnson, n. sp.

2, 028-2, 349 No algae observed.

2, 350-2, 355 Archaeolithothamnium aff. A. erythraeum (Rothpletz) Foslie, Archaeolithothamnium aff. A. 

affine Howe.

2, 355-2,440 Lithophyllum kladosum Johnson, as rodlike 

branches.

2, 440-2, 600 Lithophyllum kladosum Johnson.

2, 600-2, 802 Lithophyllum sp. A (2,655), Lithophyllum Madosum Johnson (2,680), Lithophyllum profundum 

Johnson (2,690-2,700), Archaeolithothamnium 

sp. B (2,730-2,740), Lithoporella melobesioides 

(Foslie) Foslie.

2, 802-2, 808 Archaeolithothamnium nummuliticum (Giimbel) 

Rothpletz, Archaeolithothamnium dallonii Lemoine, Lithoporella antiquitas Johnson, n. sp., 

Dactylopora? sp., Acicularia sp.

2. 808-3, 127 No algae observed.

3. 127-4, 078 No samples.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 945

Depth (feet) Drill hole F-l 

3, 665-3, 963 No samples. 

3, 963-3, 988 Lithophyllum? sp., Archaeolithothamnium eniwetokensis Johnson, n. sp. 

3, 988-4, 197 No samples__-__.____._____--__--____--_----

4, 197-4, 222

4, 222-4, 316 

4, 316-4, 341

4, 341-4, 406 

4, 406-4, 431 

4, 431-4, 500 

4, 500-4, 525

4, 525-4, 528

4, 528-4, 553

4, 553-4, 610 

4, 610-4, 630 

4, 630

Lithophyllum? sp., Archaeolithothamnium nummuliticum (Giimbel) Rothpletz, Amphiroa 

fortis Johnson, n. sp.

No samples.

Lithophyllum? sp., Archaeolithothamnium? sp., 

Jania sp. A.

No samples.

Lithothamnium? sp., Lithophyllum sp.?

No samples.

Lithothamnium crispithallus Johnson, Amphiroa 

sp. B, Corallina prisca Johnson.

No samples.

Archaeolithothamnium cf. A. sociabile Lemoine, 

Archaeolithothamnium sp. A, Archaeolithothamnium aff. A. saipanense Johnson, Lithothamnium cf. L. abrardi Lemoine, Lithothamnium 

crispithallus Johnson, Lithothamnium cymbicrusta Johnson, Amphiroa sp. A, Corallina 

prisca Johnson.

No samples; probably limestone.

Probably basalt.

Total depth.

DISTRIBUTION OF ALGAE IN BORING K-l, ENGEBI

Halimeda segments were observed at intervals 

throughout K-l (total depth 433 ft, 6 in). Eemains 

of coralline algae were found at irregular intervals but 

were only abundant at two zones. The first, from the 

surface to a depth of 33 feet, contained much algal 

debris, mainly belonging to Porolithon onkodes (Heydrich) Foslie, Porolithon craspedium (Foslie) Foslie, 

Goniolithon frutescens Foslie, Goniolithon reiriboldi 

Foslie, Goniolithon myriocarpon Foslie. The second 

zone, from 396-422 feet, contained an abundance of 

Lithoporella melol>esioides (Foslie) Foslie, and a few 

pieces of Lithoporella crassa Ishijima, Lithophyllum 

megacrustum Johnson and Ferris, and Amphiroa? sp.

DISTRIBUTION OF ALGAE IN FUNAFUTI BORING

Algae were found throughout the length of the main 

boring on Funafuti, but their distribution was not uniform. The distribution of the forms that were identified 

in the present study is given on page 946. Some zones 

were composed mostly of algae, but other zones contained only scattered fragments. At some levels the 

algae coated corals and other objects and appeared to 

be in position of growth. Elsewhere, they were represented by worn fragments which obviously had been 

transported some distance.

The abundance of algal remains in the Funafuti 

specimens seems to have been a surprise to those who

Depth (feet) Drill hole E-l

4, 078-4, 100 Algal debris, but too recrystallized to identify.

4, 100-4, 170 No samples.

4, 170-4, 190 Probably all basalt.

4, 190-4, 208 No samples.

4, 208-4, 222 Olivene basalt.

4, 222 Total depth.

made the original study, and their comments on the 

subject have been quoted many times in later works.

The slides originally prepared for the Funafuti study 

are excellent for Foraminifera and most other organisms, but are too thick to permit accurate cell measurements of the contained algae; consequently, much of 

the algal material present cannot be specifically determined. Also recrystallization occurred and this becomes pronounced in specimens from lower levels. In 

most specimens the presence of algae can be recognized 

and in many cases the genus to which they belong can 

be surmised, but recrystallization has so disturbed and 

destroyed the cellular structure that it is impossible to 

make specific determinations.

Remains of Halimeda were found throughout the 

drill holes. They were surprisingly abundant in the 

upper parts and in lagoonal deposits. Finckh, in discussing the biology of the atoll, said of Halhneda:

This calcareous algae is abundant to an extraordinarily large 

extent in the lagoon and on the ocean slopes. In order to determine its bathymetrical distribution, systematic dredgings were 

carried on off the islets of Funamanu and Falefatu, with the 

result that it was invariably found to be present alive down to 

the 45-fathom limit. Beyond that depth it was never met with 

alive, except in the case of a specimen brought up in the tangles 

on one occasion off Tutanga islet from 80 fathoms. (Finckh, 

1904, p. 135)

J. W. Judd, in discussing the materials from the 

lagoon of Funafuti, stated:
946 BIKINI AND NEARBY ATOLLS, MARSHALL ISLANDS

The dredgings in the lagoon showed that except where bosses 

of coral rock rise and form shoals, often with only a few feet 

of water upon them at high tide, the whole of the bottom of 

of the Funafuti lagoon is covered with a dense growth of the 

green calcareous algae Halimeda opuntia Lam., a well-known 

member of the order Siphoneae, group Chlorophyceae. This 

growth of Halimeda appears to be most vigorous in the shallower parts of the lagoon, but everywhere it forms a green living carpet down to depths of 120 feet, and is occasionally found 

alive at greater depths. The Halimeda fronds are often more 

or less covered with attached organisms, such as the Foraminifera Sagenina, Polytrema, etc., with Spirorbis, Serpwlae, 

Polyzoa, etc., and other organisms. Intermingled with the 

living Halimeda and its broken tunicate spicules, as well as 

remains of Pteropoda, Gastropoda, Pelecypoda, Crustaceae and 

other forms of animal life, were several forms of Lithothamnium. In the central and deeper parts the number of Foraminifera is comparatively small, seldom exceeding 10 percent 

of the whole mass, and consisting only of species adherent to 

the fronds of Halimeda, with the free forms Amphistegina and 

Heterostegina. (Judd, 1904, p. 176-177)

Professor Hinde, reporting on the material from the 

borings, stated regarding the genus Halimeda:

Detached joints of this genus are present in all the borings; 

in some portions, as for example in the Lagoon Boring, for 60 

feet below the lagoon floor, they form the greater part of the 

rock, and between 652-660 feet in the Main Boring they are 

the main constituents of the cores. As a rule their structure 

is well-preserved, so that they are readily recognized in microscopic sections. (Hinde, 1904, p. 331-332)

OCCURRENCES OP ALGAE IN FUNAFUTI BORING

Recent Porolithon onkodes (Heydrich) Foslie, Poroliihon

Reef craspedium Foslie, Porolithon gardineri Foslie,

and Goniolithon frutescens Foslie, Lithothamnium

Lagoon philippii Foslie, Lithophyllum subtilis Foslie,

Halimeda opuntia Lamarck, Halimeda cunesta

Kutzling, Halimeda tuna Lamarck, Halimeda

gracilis Harvey. 

Depth 

(feet)

0-10 Halimeda? sp.

10-20 Porolithon gardineri Foslie, Porolithon onkodes 

(Heydrich) Foslie, Lithoporella melobesioides 

(Foslie) Foslie, Halimeda? sp.

20-30 Mesophyllum erubescens (Foslie), Porolithon gardineri Foslie, Mesophyllum (Lithophyllum) australe Foslie, Halimeda sp.

60-70 Lithoporella melobesioides (Foslie) Foslie, Corallina 

sp., Halimeda sp.

80-90 Halimeda? sp.

110-120 Lithothamnium? sp., Lithophyllum? sp., Halimeda? 

sp.

210-220 Lithophyllum sp., Lithoporella melobesioides (Foslie) Foslie.

420-433 Lithophyllum sp?, Halimeda? sp.

452 Lithothamnium funafutiense Foslie, Lithoporella 

melobesioides (Foslie) Foslie.

500 Goniolithon frutescens Foslie.

526 Goniolithon fosliei (Heydrich) Foslie, Goniolithon 

frutescens Foslie, Lithoporella melobesioides (Foslie) Foslie, Lithophyllum sp., Halimeda sp.

547-555 Porolithon gardineri Foslie, Lithophyllum sp.

Depth 

(feet)

643-652 

691-698

736-748

764 

791-798

867-874

880 

891-899

950-957

973

1,006-1,015

1,087-1,100

1,100-1,114

Lithophyllum? sp., Lithoporella? sp., Halimeda sp.

Archaeolithothamnium schmidti, Foslie, Lithophyllum sp., Halimeda sp.

Archaeolithothamnium erythraeum (Rothpletz), 

Mesophyllum pulchrum (Foslie), Goniolithon 

frutescens Foslie, Halimeda sp.

Archaeolithothamnium erythraeum (Rothpletz) Foslie, Lithothamnium sp., Halimeda sp.

Porolithon cf. P. onkodes (Heydrich) Foslie, 

Lithothamnium funafutiense Foslie.

Archaeolithothamnium erythraeum (Rothpletz) Foslie, Lithophyllum sp., Halimeda sp.

Lithothamnium funa,futiense? Foslie.

Archaeolithothamnium erythraeum (Rothpletz) Foslie, Lithophyllum megacrustum Johnson and 

Ferris, Lithoporella melobesioides (Foslie) Foslie.

Goniolithon frutescens Foslie, Mesophyllum cf. M. 

australe Foslie.

Lithoporella melobesioides (Foslie) Foslie.

Lithothamnium sp., Lithophyllum sp., Halimeda sp.

Lithophyllum sp., Lithothamnium sp., Halimeda? 

sp.

Lithophyllum sp., Lithothamnium sp.

OCCURRENCES OF ALGAE IN KITA-DAITO-JIMA 

BORING

Surface Jania sp., Corallina sp., Lithoporella melobesioides 

(Foslie) Foslie, Lithophyllum megacrustum Johnson and Ferris, Lithophyllum okamurae Foslie.

17 Archaeolithothamnium puntiense Airoldi, Lithothamnium cf. L. nitidum Foslie.

23 Lithophyllum cf. L. stefaninii Airoldi, Lithophyllum 

acanthinum Foslie.

25 Lithophyllum acanthinum Foslie.

29-30 Lithophyllum quadratum Ishijima, Lithophyllum 

samoense Foslie, Lithophyllum yessoense Foslie.

37 Lithophyllum cf. L. kotschyanum Unger, Lithoporella 

melobesioides (Foslie) Foslie.

51 Archaeolithothamnium puntiense Airoldi, Lithothamnium aff. L. aucklandicum Foslie, Lithophyllum hanzawae Johnson n. sp.

60-78 Lithophyllum megacrustum Johnson and Ferris, 

Lithophyllum okamurae Foslie, Halimeda sp.

87 Halimeda sp.

115 Lithoporella?, sp. Halimeda sp.

130-135 Halimeda? sp.

160-165 Lithophyllum megacrustum Johnson and Ferris, 

Halimeda sp., Archaeolithothamnium puntiense 

Airoldi.

173 Lithothamnium aff. L. aucklandicum Foslie, Halimeda sp.

200 Lithophyllum megacrustum Johnson and Ferris, 

Halimeda? sp.

227-230 Halimeda? sp.

243 Halimeda? sp.

273 Halimeda sp.

283 Halimeda? sp.

333 Lithoporella melobesioides (Foslie) Foslie.

350 Lithophyllum cf. L. kotschyanum Unger.

367 Lithoporella sp. C, Lithophyllum acanthinum 

Foslie, Lithophyllum stefaninii Airoldi, Lithophyllum thikombian Johnson and Ferris.

380 Lithophyllum acanthinum Foslie, Microcodium sp.
FOSSIL ALGAE FROM ENIWETOK, FUNAFUTI, AND KITA-DAITO-JIMA 947

393 Lithophyllum thikombian Johnson and Ferris, 

Lithoporella melobesioides (Foslie) Foslie, Microcodium sp.

500 Lithophyllum sp. B.

513 Archaeolithothamnium puntiense Airoldi, Lithoporella melobesioides (Foslie) Foslie.

563 Dermatolithon! sp.

630 Microcodium sp.

657 Dermatolithon? sp., Jama? sp., Paraporolithon 

saipanense Johnson.

SELECTED BIBLIOGRAPHY

Airoldi, Marco, 1933, Le Corallinacee del Pleistocene della 

Somalia Italiana. VI—Fossili del Pliocene e del Pleistocene : Palaeontographica Italia, Mem. Palaeont., v. 32, supp. 

1, p. 79-96, pis. 6-7, figs. 9-11.

Barton, E. S. [Mrs. Gepp], 1901, The Genus Halimeda: SilogaExpeditie Mon. 60, p. 1-32, pis. H.

Chapman, Frederick, 1901, Foraminifera from the lagoon at 

Funafuti: Linnean Soc. London Jour. Botany, v. 28, no. 181, 

p. 161-201.

Chapman, V. J., 1955, Algal collections from Funafuti Atoll: 

Pacific Science, v. 9, p. 354-356.

Dawson, E. Y., 1944, Marine algae of the Gulf of California: 

Allan Hancock Pacific Expeditions v. 3, no. 10, 452 p., 77 

pis., Univ. Southern California Press.

————1952, Marine red algae of Pacific Mexico: Part 1. Allan 

Hancock Pacific Expeditions v. 17, no. 1, 238 p., 33 pis.

————1954, Marine plants in the vicinity of Nha Trang, Viet 

Nani: Pacific Science v. 8, no. 4, p. 373-469, 63 figs.

————1957, Annotated list of marine algae from Eniwetok,

Marshall Islands: Pacific Science, v. 11, no. 1, p. 92-132. 

Doty, M. S., 1957, Rocky intertidal surfaces, in Treatise on

marine ecology and paleoecology: Geol. Soc. America Mem.

67, v. 1, p. 535-585. 

Emery, K. O., Tracey, J. I., Jr., and Ladd, H. S., 1954, Geology

of Bikini and nearby atolls: U.S. Geol. Survey Prof. Paper

260-A, 265, pp., 64 pis. 

Finckh, A. E., 1904, Biology of the reef-forming organisms at

Funafuti Atoll: Royal Soc. Report, Atoll of Funafuti, sec.

6, p. 125-150. 

Foslie, M. H., 1909, Algologiske Notiser VI: K. norske vidensk.

selsk. Skr., no. 2, p. 1-63. 

Foslie, M. H., and Printz, Henrik, 1929, Contributions to a

monograph of the Lithothamnia: K. norske vidensk. selsk.

museet. Mon., 60 p., 75 pis. 

Gliick, Henrich, 1912, Eine neue gesteinsbildende Siphonee

(Codiacee) aus dem Marinen Tertiar von Siiddeutschland:

Mitt, der gross Badischen geol. Landesanstalt, v. 7, no. 1,

p. 1-24, pis. 1-4. 

Halligan, G. H., 1904, Report of lagoon borings, in Atoll of

Funafuti: Royal Soc. London Philos. Trans., p. 160-164. 

Hanzawa, Shoshiro, 1940-41, Micropaleontological studies of

drill cores from a deep well in Kita-Daito-Jima (North

Borodino Island) : Jubilee Publication in Commemoration

of Professor H. Yabe's Sixtieth Birthday, Geological and

Paleontological Institute, Tohoku Imp. Univ. Sci. Repts.,

v. 2, p. 755-802, pis. 39-42, Sendai, Japan. 

Hinde, G. J., 1904, Report on the materials from the borings

at the Funafuti Atoll: Section 11, Report Royal Soc., Atoll

of Funafuti, p. 186-361. 

Howe, M. A., 1919, Tertiary calcareous algae from the islands

of St. Bartholomew, Antigua, and Anguilla: Carnegie Inst.

Washington Pub. 291, p. 9-20, pis. 1-6.

Ishijima, Wataru, 1933, on three species of Corallinaceae lately 

obtained from the Megamiyama limestone, Sagara District, 

Province of Totomi, Japan: Japanese Jour. Geology and 

Geography, v. 11, nos. 1-2, p. 27-30, pis. 5.

———— 1954, Cenozoic coralline algae from the western pacific 

[Private publication] : 87 p., 49 pis., Tokyo, Japan.

Johnson, J. H., 1953, ''Microcodium" Gliick, est-il un organisme 

fossileV: Acad. sci. Paris Comptes rendus, v. 237, p. 84-86.

———— 1954a, An introduction to the study of rock building 

algae and algal limestones: Colorado School of Mines 

Quart, v. 49, no. 2, p. 117, pi. 62.

———— 1954b, Fossil calcareous algae from Bikini Atoll: U.S. 

Geol. Survey Prof. Paper 260-M, p. 537-545, pis. 188-197.

———— 1957, Geology of Saipan, Mariana Islands; calcareous

algae: U.S. Geol. Survey Prof. Paper 280-E, p. 209-243, pi.

37-60. 

Johnson, J. H., and Ferris, B. J., 1950, Tertiary and Pleistocene

coralline algae from Lau, Fiji: B. P. Bishop Mus. Bull.

201, p. 1-27, pis. 1-9. 

Judd, C. B., 1904, General report on the materials sent from

Funafuti: Report Royal Soc., Atoll of Funafuti, section

10, p. 167-185. 

Ladd, H. S., Ingerson, Earl, Townsend, R. C., Russell, Martin,

and Stephenson, H. K., 1953, Drilling at Eniwetok Atoll,

Marshall Islands: Am. Assoc. Petroleum Geologists Bull..

v. 37, no. 10 p. 2257-2280. 

Ladd, H. S. and Schlanger, S. O., 1960, Drilling operations on

Eniwetok Atoll: U.S. Geol. Survey Prof. Paper 260-Y,

p. 863-903, pis. 265-266. 

Lemoine, Mme. Paul, 1911, Structure anatomique des Melobe"-

siees : Inst. Oceanographique, Ann., v. 2, pt. 2.

———— 1928, Un nouveau genre de Melob£si£es, Mesophyllum: 

Soc. bot. France Bull., 5th ser., v. 75, p. 251-254.

———— 1939, Les algues calcaires fossiles de 1'Algerie: Mat.

Carte geol. de 1'Algerie, ser. 1, Paleont. no. 9, 128 p., 3 pis., 

80 figs.

Lemoine, J. V., 1940, Les algues calcaires de la zone n6ritique, 

from Contribution a 1'etude de la repartition actuelle et 

passee des organisms dans la zone nSritique: Soc. Biogeographie, Paul Lechevalier, Paris, v. 7, p. 75-128.

Lignac-Grutterink, L. H., 1943, Some Tertiary Corallinaceae of 

the Malaysian Archipelago: Geol.-mijnb. genootsch. Nederland en Kolonien Verh., Geol. ser., v. 113, p. 283-297, 2 pis.

Ota, Yasuski, 1938, Cores from the test drilling on Kita-DaitoJima. Examination, chemical analyses, and microscopic 

study of the Daito limestone: Institute Geol. and Paleontology, Tohoku Imp. Univ. Contr. no. 30, 25 p., 19 figs. 

[In Japanese.]

Pia, Julius, 1926, Pflanzen als Gesteinsbildner: Berlin, 355 p.

———— 1927, Die Ehrhaltung der fossilen Pflanzen, Part 1, 

Thallophyta, in Hirmer, Max, Handbuck der Palaobotanik: 

Berlin and Miinchen, p. 31-113.

Royal Society of London, 1904, The Atoll of Funafuti: Borings 

into a coral reef and the results: Being the report of the 

Coral Reef Committee of the Royal Society, 428 p., 6 pi., 

68 figs., maps.

Taylor, Wm. R., 1950, Plants of Bikini and other northern 

Marshall Islands: Mich. Univ. Studies, Sci. Ser., v. 18, 227 

p., 79 pis.

Weber van Bosse, Anna, and Foslie, M. H., 1904, The Corallinaceae of the Siboga Expedition; St&o^a-Expeditie Mon. 61, 

110 p., 16 pis., 34 figs.

Yamada, Y., 1934, The marine Chlorophyceae from Ryukyu, 

especially from the vicinity of Nawa: Hokkaido Imp. Univ. 

Fac. Sci. Jour. S. 5, v. 3, no. 2, p. 33-88, 55 figs.

INDEX

abrardi, Lithothamnium...... ______. 933,943,945

Abstract-..-._________.__________ 907 

acanthinum, Lithophyllum......... 938,943,946,pi.273

Acetabularia..... ...._._.,_..__.___ 913

Acicularia—.............................. 910,947-942

sp.. —. — — — . —.............. 941, 944, pi. 279

Acknowledgments_.__------__.____ 910

aequinoctiale, Lithophyllum. .......__.___ 934

Porolithon.. —————— — — —— 933,934, pi. 275

affine, Archaeolithothamnium... 917, 921, 943,944, pi. 269 

Age, algae as indicators of----------_----.__ 915-916

Algal ridge................................... 914,915

Amphiroa.................... 910,912,913,938,939-940

fortis.......................... 939,943,945,pi.277

medians....................... 939, 943,944,pi.278

sp.......................................... 945

sp. A.............................. 959,945, pi. 277

sp. B.............................. 939, 945, pi. 277

sp. C.............................. 940,944, pi. 278

Amphistegina................................... 946

antiquitas, Lithoporella......... 936, 937, 943,944,pi.276

araii, Lithothamnium........................... 923

arakuraensis, Mesophyllum.... 925, 943,944, pis. 270,271

Archaeolithothamnion. (See Archaeolithothamnium.) 

Archaeolithothamnium............ 910,911,912,9/5-921

affine...................... 917,9«,943,944,pi.269

chamorrosum............................... 918

crustatum...................... 917, 943,944,pi.267

dallonii.................... 917,92/, 943,944, pi. 268

eniwetokensis-—.- 917, 918, 943,944,945, pis. 267,268 

erythraeum........ 917, 919, 920, 943,944,946, pi. 268

hemchandri................ 917, 9S1, 943,944, pi. 268

intermedium................................ 917

kuboiensis.. ..............._.__..._. 918

lauense........................ 917, 943,944, pi. 267

marshallensum............ 917, 943,944,pis.267,269

megamiensis....-......................... 918,920

nummuliticum.............................. 917,

920, 921,943,944,945, pis. 268,269 

oulianovi—................... 917, 918, 919,943,944

puntiense..................... 917,9/8,943,946,947

saipanense.................... 917, 920, 921,943,945

schmidti...................... 917,9/8,919,943,946

sociabile................... 917,9/9,943,945, pi. 267

taiwanensis............ 917,9/9,920,943,944, pi. 267

timorense................................... 921

sp.......................................... 945

sp. A.......................... 917,9/9,945, pi. 267

sp. B..............._................. 917.93/.944

Arthrocardia..............................__ 910, 912

Articulate coralline algae. (See Corallinoideae.) 

aucklandicum, Lithothamnium................... 922,

923, 924, 943, 946, pi. 270 

australe, Lithothamnium......................... 927

Mesophyllum......................... 925, 9#7, 946

Mesophyllum (Lithophyllum)............... 946

australis, Lithoporella............_______... 937

Lithothamnium coralloides................... 927

Bibliography, selected___.---.._...._. 947

Bikini Atoll..-...........--.----- 907,914,943, fig. 288

bikiniensum, Lithothamnium.................... 923

Bossea.......................................... 912

Calliarthron........................____..... 912

camarasae, Lithothamnium..........______ 927

chamorrosum, Archaeolithothamnium............ 918

Charophyta____________________ 910

Cheilosporum................................... 912

Chlorophyceae___________________ 946 

Chlorophyta (green algae)........ 910, 913, 914, 941-943

(Cladolithon) frutescens, Goniolithon. ............ 932

[Italic numbers indicate description]

Page 

Classification................................. 910-912

Clathromorphum................................ 911

Codiaceae.._...---_-..--.--_..--.-----. 910, 942-943

commune, Mesophyllum........................ 927

Corallina..................... 910, 912, 913, 938, 940-941

elliptica_____________________ 941 

eniwetokensis.....-—........ 940, 943, 944, pi. 277

marshallensis.. ............... 941, 943, 944, pi. 277

neuschelorum... _____________ 941, 943, 944 

officinalis..........———— —————— 913

otsukiensis.................................. 941

prisca................................. 940,943, 945

sp..._-------..-—._._._..——_.. 946

sp. A.-...-.....-.—........... 94/, 944, pi. 277

sp. B....... —................. 941, 944, pi. 277

sp. C.--.-..—................. 941, 944, pi. 277

Corallinaceae (coralline algae).. _____ 910,916-941 

Corallinoideae (articulate coralline algae).—... 910,

912, 913, 938-941

Coralline algae. (See Corallinaceae.) 

coralloides australis, Lithothamnium............. 927

Corals._--.-..--.---.._..................... 907

craspedium, Lithophyllum....................... 934

Porolithon.................... 933,934,943,945,946

crassa, Lithoporella............ 936, 937, 943, 945, pi. 276

crispithallus, Lithothamnium.............. 933,943,945

Crustaceae..————————————.——————— 946 

crustatum, Archaeolithothamnium............... 917,

943, 944, pi. 267

Crustose coralline algae. (See Melobesioideae.) 

Cryptonemiales....—.—————.—__——— 916

cunesta, Halimeda.............................. 946

Cyanophyta (blue-green algae) ________ _ __ 910

cymbicrusta, Lithothamnium........ _.. 922,933,943,945

Cymopolia sp................................... 942

D 

Dactylopora................................... 910,941

sp--..---.-.-..-.- —.-.-- 941, 944,pis. 278,279 

dallonii, Archaeolithothamnium. 917,93/, 943,944, pi. 268 

Dasycladaceae............ 910, 913,914,915, 916, 941-942

DermatolUhon......................... 910,912,937-938

marshallensum........................ 938,pi. 277

papillosum................................. 938

saipanensum................................ 938

sp.......................................... 947

Distribution.......................... 912-915,943-946

Boring K-l, Bngebi Island.................. 945

Funafuti boring. -__--..___....__._-_. — .. 945

B 

Ecological indicators, algae as................... 916

elliptica, Corallina. _________________-------- 941

Elugelab._................................ 907, fig. 289

Engebl..—.-. — ._ — ——— —— ——— 907, 945, fig. 289

Eniwetok Atoll, Marshall Islands___...____. 907,

908,915,943, figs. 288,289

eniwetokensis, Archaeolithothamnium^........... 917,

9/8,943,944,945, pis. 267, 268 

Corallina...................... 940, 943,944,pi. 277

eniwetokensum, Mesophyllum^. 925, 926,943,944, pi. 272 

erubescens, Lithothamnium...................... 922

Mesophyllurn..............925, 928, 943,946, pi. 276

erythraeum, Archaeolithothamnium.--........... 917,

9/9,930,943,944,946, pi. 268 

Lithothamnium............................. 919

Fiji, Lau_—....... —— ................... 943, fig. 288

Foraminifera __............... 907,908,915,916,945,946

fortis, Amphiroa................... 939, 943,945, pi. 277

fosliei, Ooniolithon-.-.--...—.938, 933,943,946,pi. 275 

Lithophyllum.-............................. 932

Lithothamnium............................. 932

Foslietta—— ...... ............................. 911

frutescens, Ooniolithon... .............. 933,943,945,946

Qoniolithon (Cladolithon).. ......... . ........ 932

Funafuti Atoll, Bllice Islands— .............. 907,

908, 915, 943, 945, 946, fig. 288 

funafutiense, Lithothamnium ... 922, 934, 943, 946, pi. 270

O 

gardineri, Lithophyllum.. ....... . ........... . ... 934

Lithophyllum (Porolithon).................. 934

Porolithon ................ 914, 933, 934, 935, 943, 946

Gastropoda.-.. --------.----------.------------- 946

Geographic distribution and stratigraphic

occurrences of algae..... ._ — — —— 943-947

Goniolithon............... 910, 911, 912, 913, 933-933, 935

(Cladolithon) frutescens.... ............... ... 932

fosliei...................... 933, 933, 943, 946, pi. 275

frutescens.... ..................... 933,943,945,946

myriocarpon.. ................. 933, 943, 945, pi. 275

reinboldi.... .... ...-.-.-.. ... --------- —— - 945

gracilis, Halimeda......................... 942,943,946

Green algae. (See Chlorophyta.)

Guam...... —— ._ ——— —— _- — .- — — — — 916

H 

Hali meda. ............ 910, 913, 914, 915, 916, 943, 945, 946

cunesta---.... -------- — — —— - — — -. — — 946

gracilis-—.——.——————— 942,943,946

opuntia..... ................. -. — .--- 942,943,946

triloba----..——————— — — ——— 942

tuna———————— —— — — ———— 946

sp . ...... _ ........ 942, 943, 944, 946, pis. 279, 280

hanzawae, Lithophyllum..-...-- 938, 943, 946, pi. 272 

hemchandri, Archaeolithothamnium. ....... ——— 917,

93/, 943, 944, pi. 268 

heteroclitum, Mesophyllum.. ... ..... — —— . — 926,927

Heteroderma. ..... .... _ . — --—— — - — -. —— 911,935

Heterostegina..— .... .. ... . ————— - —————— 946

Hydrolithon-. —— ..——. —— — — - — — — — 911

intermedium, Archaeolithothamnium.— ... ... .... 917

Introduction.. _ —————————————————— 907 

irregularis, Lithophyllum .. .... . ... .. ... -------- 931

Jania... ...—————————— 910,912,913,938-939

miocenica.—— -- ————— 938, 943, 944, pi. 278

vetus— ————— — ————— 939,943,944

sp- — — — — — — — — — — — — — 946,947

sp. A_— . — - — . — — -— .— 939, 945, pi. 278 

japonicum, Mesophyllum——- 925, 936, 943, 944, pi. 271 

Joculator..--- .... — - ——————— - — - — -- — - 912

johnsoni, Lithophyllum— ............. 928, 929, 943, 944

K

Keys to the genera of the articulate coralline 

algae.-.. ————— — — -- — -- — -- — - — ---- 912

Keys to the tribes and genera of the crustose 

coralline algae.... ... — .—— —— - —— -— 911-192

Kita-Daito-Jima, Philippine Sea. . ———————— 907, 

908, 915, 943, 946, fig. 288

kladosum, Lithophyllum. 928, 931, 943, 944, pis. 272, 274 

koritzae, Mesophyllum.. ...... ... .... ----------- 925

kotschyanum, Lithophyllum... 928, 93/, 943, 946, pi. 274 

kuboiensis, Archaeolithothamnium............... 918

L

Laminariales-. _ . __ —— . — ————— ——— 910 

Larvaria sp.-... ———— ——— — — ------------- 942

lauense, Archaeolithothamnium.... 917, 943, 944, pi. 267

Lithothamnium... — ..... ..— . ...—— . —-— 923

leptum, Lithothamnium...... 922, 933, 943, 944, pi. 270

Limestone builders, algae as_.- —— ------------ 915

lingusticum, Lithophyllum.... 928, 939, 943, 944, pi. 272 

Lithophylleae- -----------.------------------- 911

949
950 INDEX

Lithophyllum......... 910, 911, 912, 925, 927-932, 933, 935

acanthinum......... ._.__ 928, 943, 946, pi. 273

aeqiiinoctiale.— -................_.___.. 934

craspedium............_.................. 934

fosliei——................................. 932

gardineri.................................... 934

hanzawae-................... 928, 943, 946, pi. 272

irregularis----.................._....... .... 931

johnsoni............... _______928,909, 943, 944

kladosum........... 928, 931, 943, 944, pis. 272, 274

kotschyanum.......... 928, 9S1, 943, 946, pi. 274

lingusticum........... 928, 929, 943, 944, pi. 272

megacrustum.—...... 928, 939, 937, 943, 945, 946

okamurae............. 928, 930, 943, 946, pi. 274

papillosum................................. 929

(Porolithon) gardineri........................ 934

prelichenoides.................... 928, 909,943,944

profundum........... 928, 931, 943, 944, pi. 275

guadratum............ 928, 930, 943, 946, pi. 273

samoense............. 928, 930, 943, 946, pi. 273

stefaninii............. 928, 930, 943, 946, pi. 273

subtilis...-__.____________.__.. 946 

tMkombian...------ 928, 930, 943, 946, 947, pi. 273

yendoi.................................. 928, 930

yessoense................................. 930, 946

sp.................................. 944, 945, 946

sp. A............................... 928, 931, 944

sp. B............................... 928, 932, 947

(Lithophyllum) australe, Mesophyllum.......... 946

Lithoporella—....................... 910, 912,935-937

antiquitas............. 936, 937, 943, 944, pi. 276

australis.................................... 937

crassa.--.......... 938, 937, 943, 945, pi. 276

longicella................. 936, 937, 943, pi. 276

melobesioides..-...- 936, 937, 943, 944, 945, 946, 947 

(Melobesia) melobesioides-................... 936

sp.-------_„--_-—.............. 946

sp. A..................... 936, 937, 944, pi. 277

sp. B................... 936, 937, 944, pi. 276

sp. C_.___.......................... 936, 937, 946

(Lithoporella) melobesioides, Mastophora......... 936

melobesioides, Melobesia....-................ 936

Llthothamnleae._____.____...___.. 911

Lithothamnion. (See Lithothamnium.)

Lithothamnium.-. 907, 910,911,912,914, 918, 937-925, 946 

abrardi-.............................. 903,943, 945

anii........................................ 923

aucklandicum....... 922, 923, 924, 943, 946, pi. 270

australe..................................... 927

bikiniensum....... ____________.... 923

camarasae.................................. 927

coralloides australis.......................... 927

crispithallus--.____________.. 903,943,945 

cymbicrusta...................... 922, 903,943,945

erubescens.................................. 926

erythraeum.................................. 919

fosliei—..................................... 932

funafutiense.———.... 922, 904, 943, 946, pi. 270

lauense.............................._.... 923

Upturn -------------- 922, 923, 943, 944, pi. 270

mirabile......................... 922, 904, 943, 944

nitidum................... 922, 924, 943, 946, pi. 270

notatum................................_... 924

nummuliticum...... ....................__ 920

onkodes. ____________.__.___ 934 

philippii.................................... 946

pulchrum................................... 927

terziari.....___...__.........._._.. 920

sp.- ——.. — ......—............. 943,945,946

sp. A.. — — ..........__._---- 922,90S, 944, pi. 269

sp. B—— .-._____________._-_ 922,90S, 944, pi. 270

sp. C—....................... 922,90S, 944, pi. 269

sp. D—....................... 922,904, 944, pi. 269

Lithotrix............................___ _.___ 912

longicella, Lithoporella............. 936,937, 943, pi. 276

M rage

Mariana Islands__________________ 915 

Marshall Islands-.-----------....----------- 915,916

marshallense, Porolithon........... 933,935, 943, pi. 275

marshallensis, Corallina............ 941, 943, 944, pi. 277

marshallensum, Archaeolithothamnium......... 917,

943,944, pis. 267, 269 

Dermatolithon—— ——————— 938, pi. 277

Mastophora..................................... 935

melobesioides.. ——— ————-_______ 935,936

(Lithoporella) melobesioides----------- .....-. 936

Measurements and distribution of species.

(tables.) 

Archaeolithothamnium-..................... 917

Lithophyllum............. ...............— 928

Lithoporella...............-------------...-. 936

Lithothamnium- _-------- —— ———— —.. 922

Mesophyllum—....——.................. 925

Porolithon.....----......-...-----......---. 933

medians, Amphiroa................ 939,943, 944, pi. 278

Mediterranean Sea.._———————. 913,915,916 

megacrustum, Lithophyllum.................... 928,

909,937, 943, 945,946 

megamiensis, Archaeolitholhamnium.-......... 918,920

Melobesia...............—————— 911, 935, 936

(Lithoporella) melobesioides..-- ...- ——— —— 936

(Melobesia) melobesioides, Lithoporella—————— 936

Melobesioideae (crustose coralline algae)——— 908,

910,911,912-913,916-938

melobesioides, Lithoporella...----- ———— ——— 935,

937, 943, 944,945,946,947

Lithoporella (Melobesia) ——— .-.-—————— 936 

Mastophora—---------------------------- 935, 936

Mastophora (Lithoporella) ————. — — —— 936 

Melobesia (Lithoporella)——................ 936

Mesophyllum.......-——— — - — . 910,911,935-927

arakuraensis............ 905, 943, 944, pis. 270, 271

australe.—————.—— —— ..——— 925,937,946 

cowTOMwe----------------------------------- 927

eniwetokensum——----- 935, 926, 943, 944, pi. 272

erubescens....——-- — . 925, 986, 943, 946, pi. 272

heteroclitum————— ——-——-—— 926, 927

japonicum- ——— .--.—— 925,905, 943, 944, pi. 271 

koritzae........................._-.-.__ 925

(Lithophyllum) australe-.................... 946

pulchrum ........—...... 925,907, 943, 946, pi. 271

robustum—------- 925, 926, 927, 943, 944,pi. 271

Sancti Dionysii........ ___-__..____ 925,926

savornini................... 925,905,943, 944, pi. 271

sp.A-- ———..._._ — — —— 925, 928, 944, pi. 271 

sp.B- —_ — —— ——— —— -—— 925,907, 944, pi. 272

Microcodium............- —— ——— —— 910,942-943

sp ------------------------- 940,944,946,947

miocenica, Jama.... ____. —— —— -_ 938, 943,944, pi. 278

mirabile, Lithothamnium--.. —...... 922,904,943,944

Mollusks——.—————— ——— —— —— ———— 907

myriocarpon, Ooniolithon............932, 943, 945, pi. 275

Neo men's — — — — — — — — ——— — — — ————— — — 913

neuschelorum, Corallina---.. — ............ 947,943,944

nitidum, Lithothamnium.--- 922,924,943,946, pi. 270 

notatum, Lithothamnium.—. — .. —..__ — __.___ 924 

nummuliticum, Archaeolithothamnium.... _ —— — 917,

900, 921, 943, 944, 945, pis. 268, 269 

Lithothamnium—. — — — ............ — ....— 920

O 

officialis, Corallina ..................... — ——— 913

okamurae, Lithophyllum,-...... 928,930,943,946, pi. 274

Okinawa—— — — — —— —------ — —— -— 913

onkodes, Lithothamnium.........—. —........... 934

Porolithon--————— 914,933,934,943,945,946 

opuntia, Halimeda.———.——————— 942,943,946

triloba, Halimeda....—-.......— ———— —— 942

otsukiemis, Corallina............................ 941

oulianovi, Archaeolithothamnium,-- 917,978,919,943,944

Palaulslands—— ——————— — --— 916, fig. 288

papillosum, Dermatolithon...................... 938

Lithophyllum-.............................. 929

Paraporolithon............................ 910,911,935

saipanense... — ...——________ 935,943,947 

Parry Island...————— — ..————. 907, fig. 289

Pelecypoda__._——_______-------_ 946

Peliliu———......... —— ..—— — — — — 916

Phaeophyta (brown algae)-____......_ — - 910

philippii, Lithothamnium. —......__......... 946

Polytrema...................................... 946

Polyzoa- ——— ———————— — — —— 946

Porolithon- —— ——— 910, 911, 912, 913, 914,932, 933-935 

aequinoctiale .............__ 933,934,943,pi.275

craspedium.---------- 933,934,943,945,946

gardineri.....———— -.. 914,933,934,935,943,946

marshallense. — ...—. —...... 933,9.35,943,pi.275

onkodes..... —————. 914,933,934,943,945,946

sp-- —...... ——— ——— ————— ———...... 943

(Porolithon) gardineri, Lithophyllum............. 934

Porostromata—— —— ——— ——————————— 910

prelichenoides, Lithophylum.—....... 928, 909, 943, 944

prisca, Corallina--.......————........ 940,943,945

Procedure————————————— 908-909

profundum, Lithophyllum-.-- 928, 937, 943, 944, pi. 275 

Pteropoda_____---------—————————— 946

pulchrum, Lithothamnion.-----------..--------- 927

Mesophyllum....——- 925, 907, 943, 946, pi. 271

puntiense, Archaeolithothamnium~.917,918, 943, 946,947

Q,R

quadratum, Lithophyllum—— 928, 930, 943, 946, pi. 273

Red algae. (See Rhodophyta.)

reinboldi, Goniolithon.... - — - —— ------ — —— — 945

Rhodophyceae—- —- ——— —— — — —— —— - 916

Rhodophyta (red algae)------------------—- 910,916

Ridge, algal....———————-- —— — — - 914,915

robustum, Mesophyllum.. 925, 926, 927, 943, 944, pi. 271 

Ryukyu Islands.. —————— ————— 913, 914

S 

Sagenina....................................... 946

Saipan.-..--------------------------------- 907,943

saipanense, Archaeolithothamnium............... 917,

900, 921, 943, 945 

Paraporolithon....-----.--.....--.---- 935, 943, 947

saipanensum, Dermatolithon---. ...——___.. 938

samoense, Lithophyllum-..... 928, 930, 943, 946, pi. 273

Sancti Dionysii, Mesophyllum—-———___ 925,926 

savornini, Mesophyllum...... 925, 906, 943, 944, pi. 271

schmidti, Archaeolithothamnium... 917, 918, 919, 943, 946 

Serpulae........... —— ———— ——— —. ——.— 946

sibogae, Archaeolithothamnium—....._____ 918

Siphoneae.. — —. — ————— —— -------------- 946

sociabile, Archaeolithothamnium---..-. ...___ 917,

919, 943, 945, pi. 267 

Solenoporaceae—-__———-—— ——____... 910

Source of material. _______________ 907-908 

Spjror6zs-—--------------------------------- 946

Spongiostromata.--------- — - —— ———. ——. 910

stefaninii, Lithophyllum--.--. 928, 930, 943, 946, pi. 273 

subtilis, Lithophyllum.-...... ...-——_____ 946

Systematic descriptions__ — _--------_— 916-943

T-Y

taiwanensis, Archaeolithothamnium— ——— —... 917, 

919, 920, 943, 944, pi. 267

terziari, Lithothamnium. —— —.———___— 920 

thikombian Lithophyllum... 928,930, 943, 946, 947, pi. 273 

timorense, Archaeolithothamnium................ 921

triloba, Halimeda opuntia.........——_____ 942

tuna, Halimeda---...-.------.-------.-------.-. 946

Ulithi Atoll--- ——————————— — — 916

vetus, Jania—--------- ---------------- 939,943,944

yendoi, Lithophyllum...... _____._____ 928,930

yessoense, Lithophyllum.--.------............. 930,946

O
PLATES 267-280
PLATE 267

FIGURES 1-2. Archaeolithothamnium crustatum Johnson, n. sp. (p. 917).

1. A perpendicular section through the crust, X 95. Shows a narrow irregular hypothallus, a well-developed perithallus, and a number of sporangia. Miocene. Eniwetok. Holotype USNM 51424.

2. Specimen showing the irregular hypothallus at the base and a crust made of several superimposed thalli, X 48.

Miocene. Eniwetok. USNM 51425. 

3, 4. Archaeolithothamnium cf. A. sociabile Lemoine (p. 919).

3. A fragment showing part of the perithallus with numerous sporangia, X 48. Late Eocene. Eniwetok. USNM 

51431.

4. Specimen giving details of the tissue and sporangia, X 48. Late Eocene. Eniwetok. USNM 51432.

5. Archaeolithothamnium marshallensum Johnson, n. sp. (p. 917).

A section of a crust showing a slightly developed hypothallus, and the perithallic tissue with a cluster of sporangia, 

X 48. Miocene. Eniwetok. Holotype. USNM 51427.

6. Archaeolithothamnium eniwetokensis Johnson, n. sp. (p. 918).

Section of crust, with a hypothallus consisting of a few curved rows of cells; fairly regular perithallic tissue and a 

row of sporangia, X 48. Miocene. Eniwetok. Holotype USNM 51429.

7. Archaeolithothamnium cf. A. taiwanensis Ishijima (p. 919).

Oblique section through a small fragment, X 95. Miocene. Eniwetok. USNM 51433.

8. Archaeolithothamnium lauense Johnson and Ferris (p. 917).

Section showing the relatively thick basal hypothallus, the regular well-developed perithallus, and two rows of 

sporangia, X 48. Miocene. Eniwetok. USNM 51426.

9. Archaeolithothamnium sp. A. (p. 919).

Oblique section of a thin slightly recrystallized crust with sporangia. Part of alga is growing around an encrusting 

foraminifer, X 48. Late Eocene. Eniwetok. USNM 51434.
GEOLOGICAL SURVEY

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PROFESSIONAL PAPER 260 PLATE 267

ARCHAEOLITHOTHAMNIUM
PLATE 268

FIGURE 1. Archaeolithothamnium eniwetokensis Johnson, n. sp. (p. 918).

Detail of hypothallus and perithallus, X 95. Miocene. Eniwetok. USNM 51430. 

2, 3. Archaeolithothamnium erythraeum (Rothpletz) Foslie (p. 919).

2. Section of a considerably recrystallized specimen giving a general idea of the thallus and the sporangia, X 38. 

Pleistocene or Recent. Funafuti. British Museum slide 773.

3. Recrystallized specimen showing thin crust with numerous sporangia X 38. Pleistocene or Recent. Funafuti. 

British Museum slide 773.

4. Archaeolithothamnium aff. A. erythraeum (Rothpletz) Foslie (p. 920).

Detail of perithallic tissue and sporangial cavities, X 95. Miocene. Eniwetok. USNM 51435.

5. Archaeolithothamnium dallonii Lemoine (p. 921).

Slightly oblique longitudinal section of a branch showing the tissue and scattered sporangia, X 48. Late Eocene. 

Eniwetok. USNM 51439.

6. Archaeolithothamnium nummuliticum (Giimbel) Rothpletz (p. 920).

Section through a knobby crust, at the base is a fairly well developed hypothallus with curved cell rows, another patch 

of hypothallic tissue near the center probably represents scar tissue; a well-developed perithallus with sporangia is 

at the top, X 48. Late Eocene. Eniwetok. USNM 40813.

7. Archaeolithothamnium cf. A. hemchandri Rao (p. 921).

A vertical section of a fragment consisting of perithallic tissue containimg some sporangia, X 95. Late Eocene. Eniwetok. USNM 51437.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 268

ARCHAEOLITHOTHAMNIUM
PLATE 269

FIGURE 1. Archaeolithothamnium aff. A. affine Howe (p. 921).

Part of a branch showing the vertical cell rows, the curved growth zones, and several layers of sporangia, X 38. 

Miocene. Eniwetok. USNM 51438.

2. Archaeolithothamnium nummuliticum (Gtimbel) Rothpletz (p. 920).

Section through a crust the bottom of which is badly reerystallized, X 48. Several layers of sproangia are visible 

and some details of the outer perithallic tissue. Late Eocene. Eniwetok. USNM 40810.

3. Archaeolithothamnium marshallensum Johnson, n. sp. (p. 917).

A thin crust, X 48. Consists almost entirely of perithallic tissue with a few sporangia. Miocene. Eniwetok.

USNM 51428. 

4, 5. Lithothamnium sp. D (p. 924).

4. Fragment of a slender branch with well-defined medullary hypothallus and a slender marginal perithallus, 

X 48. Miocene. Eniwetok. USNM 40922.

5. A slightly oblique section (X 48) of another branch showing more details of the marginal perithallus than fig. 4.

Early Miocene. Eniwetok. USNM 40804. 

6, 7. Lithothamnium sp. C (p. 923).

6. Section of a crust, X 48. Hypothallus thin and irregular with curved rows of cells with a thicker perithallus 

above. Miocene. Eniwetok. USNM 40802.

7. Specimen, X 48. Slightly oblique section showing details of hypothallus. Miocene. Eniwetok. USNM 40803. 

8. Lithothamnium sp. A (p. 923).

Thin irregular crust, X 48. Miocene. Eniwetok. USNM 40800.
GEOLOGICAL SURVEY

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PROFESSIONAL PAPER 260 PLATE

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ARCHAEOLITHOTHAMNIUM AND LITHOTHAMNIUM
PLATE 270

FIGURE 1. Liihoihamnium funafutiense Foslie (p. 924).

Thin crust showing the hypothallus and perithallus, X 38. Pleistocene. Funafuti. British Museum slide 534. 

2. Lithothamnium sp. B (p. 923).

Shows the well-developed hypothallus and the relatively thin perithallus, X 95. Miocene. Eniwetok. USNM

40801. 

3, 4. Lithothamnium cf. L. nitidum Foslie (p. 924).

3. Section of a crust with a thin hypothallus of curved rows of cells, a thick perithallus and a conceptacle chamber 

(near top) having indications of multiple openings in the roof of the conceptacle, X 38. Probably Pleistocene. 

Kita-Daito-Jima. Tohoku University, slide 53.

4. Specimen showing irregular growth zones and a conceptacle chamber with several apertures, X 95. Probably 

Pleistocene. Kita-Daito-Jima. Tohuko University, Aoki coll., slide 196.

5. Mesophyllum cf. M. arakuraensis Ishijima (p. 925).

Section of a large crust with well-developed coaxial hypothallus, a thick perithallus and a conceptacle chamber 

showing several apertures (upper left), X 48. Miocene. Eniwetok. USNM 40805.

6. Lithothamnium aff. L. aucklandicum Foslie (p. 923).

Shows irregular growth zones of the perithallic tissue and four conceptacles filled with sporangia, X 71. Pleistocene (?). Kita-Daito-Jima. Tohoku University, slide 124.

7. Lithothamnium Upturn Johnson and Ferris (p. 923).

Crust with moderately developed hypothallus at the base, and a thicker perithallus above, X 48. Miocene. Eniwetok. USNM 40799.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 270

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LITHOTHAMNIUM AND MESOPHYLLUM
PLATE 271

FIGURE 1. Mesophyllum cf. M. arakuraensis Ishijima (p. 925).

Slightly recrystallized specimen showing hypothallus and perithallus, X 48. Miocene. Eniwetok. USNM 40806.

2. Mesophyllum japonicum Ishrjima (p. 926).

Several specimens intergrown, X 48. A good basal hypothallus occurs near the bottom overlain by a thick perithallus 

with irregular growth zones. Miocene. Eniwetok. USNM 40809.

3. Mesophyllum sp. A (p. 926).

Slightly oblique section of a crust with a well-developed basal hypothallus and a thick perithallus composed of a 

number of irregular growth zones, X 48. Miocene. Eniwetok. USNM 40808.

4. Mesophyllum cf. M. savornini Lemoine (p. 926).

Section of a badly recrystallized branch containing three cavities of conceptacle chambers, X 48. Miocene. Eniwetok. 

USNM 40944.

5. Mesophyllum pulchrum (Foslie) Lemoine (p. 927).

Section of badly recrystallized branch with thick irregular growth zones and several conceptacle chambers, X 38. 

Pleistocene. Funafuti. British Museum slide 688.

6. Mesophyllum robustum Johnson, n. sp. (p. 926).

Section of a crust showing a well-developed coaxial hypothallus and a thick irregular perithallus with pronounced 

growth zones, X 95. Several conceptacles with traces of the sporangia are present. Late Eocene. Eniwetok. 

Holotype USNM 40812.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 271

MESOPHYLLUM
PLATE 272

FIGURE 1. Lithophyllum cf. L. lingusticum Airoldi (p. 929).

A thin crust (X 48) composed of a well-developed hypothallus with a thin perithallus. Late Eocene. Eniwetok.

USNM 40814. 

2, 3. Lithophyllum hanzawae, Johnson n. sp., (p. 928).

Pleistocene (?), Kita-Daito-Jima. Holotype, Tohoku University slide, Aoki colln. 141.

2. Detail of the hypothallus, perithallus, and conceptacle chambers, X 95.

3. General view showing the thick regular perithallic tissue and the numerous conceptacle chambers, X 38. The 

large single apertures of some of the conceptacles are plainly visible.

4. Mesophyllum eniwetokensum Johnson, n. sp. (p. 925).

Slightly oblique section of a crust formed of several superimposed thalli, X 48. Shows growth zones and several 

conceptacle chambers with traces of the sporangia. Miocene. Eniwetok. Holotype, USNM 40807.

5. Mesophyllum sp. B. (p. 927).

Section of a branch giving details of the tissue, X 48. Miocene. Eniwetok. USNM 40811.

6. Mesophyllum erubescens (Foslie) Lemoine (p. 926).

A part of the tissue of a branch, X 38. Pleistocene or Recent. Funafuti. British Museum slide 615.

7. Lithophyllum kladosum Johnson (p. 931).

Section showing branching, X 48. Miocene. Eniwetok. USNM 40924.
PROFESSIONAL PAPER 260 PLATE 272

4 7 

LITHOPHYLLUM AND MESOPHYLLUM
PLATE 273

FIGTJKE 1. Lithophyllum acanthinum Foslie (p. 928).

Badly frayed crust showing well-developed hypothallus and perithallus, X 95. Pliocene or Pleistocene. KitaDaito-Jima. Tohoku University slide 656. 

2. Lithophyllum quadratum Ishijima (p. 930).

Section of a crust composed of several superimposed thalli, X 38. Each consists of a thin hypothallus and a

thicker perithallus with regular tissue. Pleistocene(?). Kita-Daito-Jima. Tohoku University slide 63. 

3, 4. Lithophyllum stefaninii Airoldi (p. 930).

Probably Pliocene-Pleistocene. Kita-Daito-Jima. Tohoku University slides 62 and 661.

3. Thin irregular crust showing the regular perithallic tissue and poorly developed hypothallus, X 38.

4. Slightly oblique section of crust with well-developed hypothallus, X 38. 

5, 6. Lithophyllum samoense Foslie (p. 930). 

Pleistocene (?). Kita-Daito-Jima.

5. Section through a thick crust showing several conceptacle chambers, X 71. Tohoku University slide 61.

6. Section of thin crust with a thin hypothallus at the base and a thick perithallus with several conceptacle chambers,

X 38. Tohoku University slide 256. 

7. Lithophyllum thikombian Johnson and Ferris (p. 930).

Fragment showing well-developed coaxial hypothallus and parts of a narrow perithallus, X 95. Probably Miocene.

Kita-Daito-Jima. Tohoku University slide 656.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 273

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PLATE 274

FIGURE 1. Lithophyllum okamurae Foslie (p. 930).

Section of a fertile crust with thick perithallic tissue and numerous small conceptacle chambers, X 38. Pleistocene or Recent. Kita-Daito-Jima. Tohoku University slide 176. 

2, 3. Lithophyllum cf. L. kotschyanum linger (p. 931).

Pleistocene (?). Kita-Daito-Jima. Tohoku University slide 73.

2. Section of a large and partly recrystallized branch, X 38. Numerous growth zones and 

several conceptacle chambers are shown.

3. Slightly oblique section of branch showing transition from medullary hypothallus to 

marginal perithallus as well as pronounced growth zones and several small conceptacle 

chambers, X 38. 

4, 5. Lithophyllum kladosum Johnson (p. 931).

Miocene. Eniwetok.

4. Section of a typical long slender branch bearing two conceptacles along the outer margin, 

X 48. USNM 40816.

5. Specimen showing the development of branches, X 48. USNM 40815.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 274
PLATE 275

FIGURES 1, 2. Porolithon aequinoctiale (Foslie) Foslie (p. 934). 

Pleistocene(?), and Recent. Eniwetok.

1. Section of perithallic tissue perpendicular to the cell layers showing the clusters of megacells, X 95. USNM 

40817.

2. Section parallel to the cell layers showing the megacell clusters in ground plan, X 95. USNM 40818. 

3, 4. Porolithon marshallense Taylor (p. 935). 

Recent. Eniwetok.

3. Oblique section through the tip of a branch showing the medullary hypothallus, and the marginal perithallic 

tissue with numerous clusters of megacells, X 48. USNM 40819.

4. Section through branch showing details of tissue X48. USNM 40940.

5. Lithophyllum profundum Johnson (p.. 931).

Branch with a marginal conceptacle, X 48. Miocene. Eniwetok. USNM 40913.

6. Goniolithon myriocarpon Foslie (p. 932).

Recent and Miocene. Eniwetok. Section of crust with a thin basal hypothallus and a thicker perithallus, X 48. 

Numerous megacells are distributed throughout penthallic tissue. USNM 40820.

7. Goniolithon fosliei (Heydrich) Foslie (p. 932).

Thin crust, somewhat re crystallized, with a well-developed coaxial hypothallus and a thicker perithallus, X 95. 

The small megacells are not clearly shown. Recent and Pleistocene (?). Funafuti. British Museum slide 665.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 275

7 4 

POROLITHON, GONIOLITHON, AND LITHOPHYLLUM
PLATE 276

FIGURES 1, 2. Lithoporella antiquitas Johnson, n. sp. (p. 937).

Vertical sections of fertile specimens showing the long canal leading to the conceptacle opening, X 95. Miocene. Eniwetok. Holotype USNM 40825. 

3, 4. Lithoporella longicella Johnson n. sp. (p. 937).

Nearly vertical sections showing crusts formed of numerous thalli superimposed, X 48. 

Recent or Pleistocene(?). Eniwetok. Holotype USNM 40822.

5. Lithoporella sp. B (p. 937). Section, X 48. Miocene. Eniwetok. USNM 40824.

6. Lithoporella cf. L. crassa Ishijima (p. 936). The section cuts a number of superimposed thalli 

at various angles, X 48. Recent or Pleistocene (?) Eniwetok. USNM 40821.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 276

LITHOPORELLA
PLATE 277

FIGURE 1. Corallina sp. B (p. 941).

Two segments, X 48. Miocene. Eniwetok. USNM 40832. 

2, 3. Corallina marshallensis Johnson, n. sp. (p. 941). 

Miocene. Eniwetok.

2. Two segments with a node between, X 48. Holotype USNM 40829.

3. A single segment, X 48. USNM 40830.

4. Corallina sp. C (p. 941).

Nearly complete segment, X 48. Miocene. Eniwetok. USNM 40833.

5. Corallina sp. A (p. 941).

Worn segment, X 48. Miocene. Eniwetok. USNM 40831.

6. Amphiroa sp. A (p. 939).

Long segment somewhat abraded, X 38. Late Eocene. Eniwetok. USNM 40945.

7. Amphiroa sp. B (p. 939).

Fragment showing alternating layers of long and short cells, X 95. Late Eocene. Eniwetok. USNM 40914. 

8, 9. Amphiroa fortis Johnson, n. sp. (p. 939). 

Late Eocene. Eniwetok.

8. Worn piece of a large segment, X 48. Paratype, USNM 40835.

9. Nearly complete segment showing a little of the marginal perithallus as well as the thick medullary hypothallus, X 38. Holotype USNM 40834. 

10—12. Corallina eniwetokensis Johnson, n. sp. (p. 940). 

Miocene. Eniwetok.

10. Several worn fragments cut at various angles, X 48. Paratype USNM 40827.

11. Several pieces, one shows a complete segment, a node, and character of the branching, X 48. Paratype 

USNM 40827.

12. Three segments with the intervening nodes, X 48. Holotype USNM 40828.

13. Dermatolithon marshallensum Johnson, n. sp. (p. 938).

Several specimens, one bearing a conceptacle, X 48. Miocene. Eniwetok. Holotype USNM 40826.

14. Lithoporella sp. A (p. 937). 

' " Small piece of a young plant, X 48. Miocene. Eniwetok. USNM 40823
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 277

13 14 11 

CORALLINA, AMPHIROA, DERMATOLITHON, AND LITHOPORELLA
PLATE 278

FIGURES 1-3. Amphiroa medians Johnson, n. sp. (p. 939). Miocene. Eniwetok.

1. Segment showing character of branching, X 48. USNM 40915.

2. A larger segment with branch, X 48. Holotype USNM 40923.

3. Several worn fragments, X 48. USNM 40809.

4. Jania sp. A (p. 939).

A nearly complete segment, X 48.

Late Eocene. Eniwetok. USNM 40916.

5. Amphiroa sp. C (p. 940).

A branching segment, X 48. Miocene. Eniwetok. USNM 40917. 

6-8. Jania miocenica Johnson, n. sp. (p. 938). 

Miocene. Eniwetok.

6. A long segment, X 48. USNM 40918.

7. A slightly oblique section of a small segment, X 48. Holotype USNM 

40919.

8. A fragment of a terminal segment showing a conceptacle chamber,

X 48. Holotype USNM 40919. 

9-12. Dactylopora? sp. (p. 941).

Random sections of worn fragments, X 24. Late Eocene. Eniwetok. 

USNM 40920 (figs. 10, 11, 12) and USNM 40921 (fig. 9).
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 278

AMPHIROA, JANIA, AND DACTYLOPORA
PLATE 279

FIGURE 1. Halimeda segments and coralline algae, X 14. (p. 942).

Pleistocene (?). Kita-Daito-Jima. 

2. Halimeda segments in limestone, X 1. (p. 942).

Pleistocene(?). Eniwetok. USNM 40941. 

3-5. Dactylopora? sp. (p. 941). 

Late Eocene. Eniwetok.

3, 4. Nearly tangential sections, X 24. USNM 40942. 

5. A longitudinal section near the outer margin, X 24.

USNM 40921. 

6, 7. Acicularia sp. (p. 941).

Numerous unoriented fragments scattered over the slides, X 14. Late Eocene. 

Eniwetok. USNM 40944.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 279

6 7 

HALIMEDA, DACTYLOPORA, AND ACICULARIA
PLATE 280

FIGUEES 1-2. Numerous segments of Halimeda cut at various angles, X 14. (p. 942).

Pleistocene (?). Kita-Daito-Jima.

3-4. Segments of Halimeda badly recrystallized, X 38. (p. 942). 

Pleistocene or Recent. Funafuti core.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 260 PLATE 280

HALIMEDA