The Brachiopod Genera Hebertella, 

Dalmanella, and Heterorth'ina from 

The Ordovician of Kentucky 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 1066-M 

Prepared in cooperation with the 

Commonwealth of Kentucky, 

Unz'versz'ty of Kentucky, 

Kentucky Geological Survey 
The Brachiopod Genera Hebertella, 

Dalmanella, and Heterorth'ina from 

The Ordovician of Kentucky 

By LAURENCE G. WALKER 

CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF 

KENTUCKY AND NEARBY STATES 

Edz"ted by JOHN PO JET A, JR. 

GEOLOGICAL SURVEY PROFESSIONAL PAPER 1066-M 

Prepared t"n coopera#on wz"th the 

Commonwealth of Kentucky, 

Un£vers£ty of Kentucky, 

Kentucky Geologt"cal Survey 

A taxonomt"c study of nt"ne spect"es and 

thet"r stratt"grapht"c distrt"butt"on t"n the 

Lext"ngton Lz"mestone and younger 

Ordouict"an ·rocks 

U N I T ED S T AT E S G 0 V E R N M EN T P R I NT I N G 0 F F I C E, W AS H I N G T 0 N : 1 9 8 2 
UNITED STATES DEPARTMENT OF THE INTERIOR 

JAMES G. WATT, Secretary 

GEOLOGICAL SURVEY 

Dallas L. Peck, Director 

Library of Congress Cataloging in Publication Data 

Walker, Laurence G. (Laurence Graves), 1937-

The brachiopod genera Hebertella, Dalmanella, and Heterorthina from the Ordovician of Kentucky. 

(Contributions to the Ordovician paleontology of Kentucky and near,by states) (Geological Survey professional paper ; 

1066-M) 

"Prepared in cooperation with the Commonwealth of Kentucky, University of Kentucky, Kentucky Geological Survey." 

Bibliography: p. 

Supt. of Docs. no.: I 19.16:1066-M) 

1. Hebertella. 2. Dalmanella. 3. Heterorthina. 4. Paleontology-Ordovician. 5. Paleontology-Kentucky. I. Title. 

II. Series. III. Series: Geological Survey professional paper; J066-M. 

QE797. 7W34 564 '.8 82-600093 

For sale by the Distribution Branch, U.S. Geological Survey, 

604 South Pickett Street, Alexandria, VA 22304 

AACR2 
CONTENTS 

Page 

Abstract--~------------------------------------------------------------------- ~1 

Introduction------------------------------------------------------------------- 1 

Acknowledgments-----------------------------------------------------~----- 1 

Systematic paleontology--------------------------------------------------------- 2 

Genus Hebertella 2 

Hebertella frankfortensis Foerste -------------------------------------------- 3 

Hebertella occidentalis (Hall) ----------------------------------------------- 6 

Hebertella parksensis Foerste ----------------------------------------------- 8 

Genus Dalmanella 9 

Dalmanella bassleri Foerste ------------------------------------------------ 1i 

Dalmanella fertilis (Ulrich)------------------------------------------------- 11 

Dalmanella meeki (Miller)-------------------------------------------------- 12 

Dalmanella multisecta (Meek) ---------------------------------------------- 12 

Dalmanella sulcata Cooper------------------------------------------------- 13 

Genus Heterorthina 13 

Heterorthina macfarlani Neuman ------------------------------------------- 14 

Locality register --------------------------------------------------------------- 14 

Referencescited---------------------------------------------------------------- 16 

ILLUSTRATIONS 

[Plates follow references cited) 

PLATES 1-2. Dalmanella. 

3. Dalmanella and Heterorthina. 

4. Heterorthina and Hebertella. 

5. Hebertella. 

SYSTEM OF MEASUREMENT UNITS 

The investigations underlying this series of reports were made over a period of years, and distances and stratigraphic measurements appear fairly uniformly in English, units. ~easurements offossilspecimens, on the other hand, follow the longstanding convention of appearing 

in metric units. Because of the dates of the investigations and the amount of resulting data, the English measurements have been retained. 

Conversions to metric units may be made by using the following conversion table: 

To convert English unit: 

~ile (mi) 

Foot (ft) 

Inch (in.) 

To metric unit: 

Kilometer (km) 

~eter (m) 

Centimeter (em) 

~ultiply by: 

1.61 

.305 

.394 

Ill 

CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

THE BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND 

HETERORTHINA FROM THE ORDOVICIAN OF KENTUCKY 

By LAURENCE G. WALKER 1 

ABSTRACT 

The orthid brachiopod genera Hebertella, Dalmanella, and Heterorthina are abundant in Middle and Upper Ordovician strata in Kentucky. 'Nine species are described: Hebertella frankfortensis Foerste; 

H. parksensis Foerste; H. occidentalis (Hall); Dalmanella bassleri 

Foerste; D. fertilis (Ulrich); D. meeki (Miller); D. multisecta (Meek); D. 

sulcata Cooper; and Heterorthina macfarlani Neuman. The species 

designations Hebertella sinuata (Hall), H. subjugata (Hall), and H. 

latasulcata Foerste are placed in synonymy with H. occidentalis 

(Hall). The stratigraphic distribution of each species is given. 

Large collections of silicified specimens allowed the recognition 

of the considerable variability characteristic of most of the species. 

External morphology distinguishes species of Hebertella, whereas 

internal features are critical to recognition of species of Dalmanella 

and Heterorthina. 

INTRODUCTION 

Orthid brachiopods are abundant in Middle and 

Upper Ordovician rocks in central Kentucky and adjacent areas. A knowledge of their taxonomy and distribution is important for an understanding of the biostratigraphy of this reference area for the Upper 

Ordovician rocks of North America. The purpose of this 

paper is to describe the taxonomy and distribution of 

the common genera Hebertella, Dalmanella, and Heterorthina, to present interpretations regarding their evolution, and to assess their possible value in correlation. 

The other common orthid in this area is the genus Platystrophia; it was treated by Alberstadt (1979). 

The study specimens were collected by staff members of the U.S. Geological Survey. Almost all collections were made in the Ordovician outcrop area of 

central Kentucky, although a few collections came from 

the adjacent States of Indiana, Ohio, and Tennessee. 

'Hrubetz Oil Company, Lafayette, La. 

Most collections are of silicified specimens, which 

were extracted from limestone by acid in the laboratories of the Geological Survey in Washington, D.C., 

and sent to me. Many collections from single beds contain scores or hundreds of well-preserved specimens. 

Good concepts of the orthid species were obtained from 

these large collections because infraspecific variability 

could be seen and evaluated. However, information on 

the geographic and stratigraphic distribution of species 

in the study area is limited. In general, collections were 

made from silicified beds, and no systematic sampling 

was done from thin intervals of all lithologies in a particular section. Silicified beds are so common that a 

good coverage of the Ordovician strata was obtained 

and the general stratigraphic ranges could be established. Significant gaps do exist, however, and the data 

and interpretations given herein concerning distribution and evolution are necessarily circumscribed. On 

the basis of the available information, nothing can be 

said regarding possible facies control of species. 

Complex facies patterns exist in the Ordovician sequence in Kentucky. In determination of the stratigraphic ranges of species, I used the stratigraphic 

framework and correlations as interpreted by the U.S. 

Geological Survey staff(Black and others, 1965; Cressman and Karklins, 1970; Weir and Greene, 1965; Weir 

and others, 1965; Peck, 1966; Simmons and Oliver, 

1967; Black and Cuppels, 1973; and Cressman, 1973). 

Pojeta (1979) has summarized the Ordovician stratigraphy of Kentucky and adjacent States. 

ACKNOWLEDGMENTS 

Financial assistance for this study was provided by 

two Faculty Research Grants at Memphis State University, Memphis, Tenn. I am grateful to the following 

Ml 
M2 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

persons for the loan of type specimens: Thomas E. Bolton of the Geological Survey of Canada, Ottawa; Roger . 

L. Batten of the American Museum of Natural History, 

New York; and Frederick J. Collier of the Smithsonian 

Institution, Washington, D.C. I especially appreciate 

the considerable aid and encouragement of the editor 

of this project, John Pojeta, Jr., of the U.S. Geological 

Survey, Washington, D.C. 

SYSTEMATIC PALEONTOLOGY 

Phylum BRACHIOPODA Dumeril 

Class ARTICULATA Huxley 

Order OR THIDA Schuchert and Cooper 

Superfamily ORTHACEA Woodward 

Family PLECTORTHIDAE Schuchert and Levene 

Genus HEBERTELLA Hall and Clarke, 1892 

Type species.-Orthis sinuata Hall, 184 7, p. 128, by 

original designation. 

Description.-Adult shells 15 to 50 mm wide, 10 to 

40 mm long; outline subquadrate to subelliptical; 

maximum width generally between hinge and midlength. Hinge straight, cardinal extremities generally 

rounded or angular but can be alate; pedicle valve interarea large, curved, apsacline, or rarely straight and 

catacline; brachial valve interarea smaller, curved, orthocline to apsacline, rarely anacline. Lateral profile 

unequally biconvex or convexo-concave; pedicle valve 

concave if beak erect and interarea near catacline; 

brachial valve strongly curved with maximum depth 

near or anterior to midlength; pedicle valve slightly 

curved in posterior part to flat or concave in anterior 

part, maximum depth within posterior one-third of 

valve. Anterior margin weakly to strongly uniplicate, 

brachial valve fold weak to strong, pedicle valve sulcus 

weak to strong. Ribs numerous, 14 to 20 developing 

from protegulal node, others developing lateral to beak 

on posterior edge of valve surface, tubulose and increasing in number by bifurcation. 

Pedicle valve interior with prominent teeth, strong 

dental plates, and well-developed crural fossettes. Urnbona! cavity deep, muscle scars obvious because of 

narrow marginal ridge or because deeply impressed; 

muscle field elongate cordate; adductor scars elongate 

suboval, borne on median double ridge; wide diductor 

scars subcrescentric, extending beyond adductor ridges 

but not enclosing adductor scars; pedicle adjustor muscle scars may be present at base and sides of dental 

plates. Pedicle callist present in thickened valves. 

Amount of secondary thickening variable, mainly 

around muscle field; wavy elevated lines commonly 

present in thickened areas on each side of muscle field. 

Brachiophores and brachiophore bases convergent 

toward floor of brachial valve, curving toward midline 

near junction with prominent notothyrial platform. 

Curved fulcra! plates forming floor of sockets. Cardinal 

process bladelike, may be slightly thickened along 

anteroventral edge; myophore thin, crenulated, located 

posterior to anteroventral edge of shaft, which extends 

higher as a thickened or bulblike structure. Median 

ridge extending anteriorly from notothyrial platform 

and ranging from slightly elevated to prominent, 

reaching as far forward as one-third length of valve. 

Muscle scars indistinguishable to faintly impressed on 

larger valves; posterior pair larger than anterior pair; 

scars subelliptical with long axes oriented about 30 o to 

midline; median ridge commonly extending to within 

adductor-scar areas; laterally directed branches of 

median ridge may exist between posterior and anterior 

scars in larger valves. Radial elevated lines are generally marginal to socket area and posterior muscle scars 

in large valves. 

Discussion.-The name Hebertella has been applied 

in the past to species of several genera, particularly 

J?lectorthis, Mimella, Glyptorthis, Eridorthis, and 

Austinella. External similarities were the chief reason 

for this; generally, each of these genera is readily distinguished on the basis of internal structures. The last 

three genera were originally included in Hebertella by 

Hall and Clarke (1893) but were later separated by 

Foerste (1909a, 1914a). 

The principal diagnostic features of Hebertella are 

its pedicle-valve muscle field, with the double adductor 

ridge, and the profile of the pedicle valve, which is only 

slightly convex or even flat to concave. Plectorthis is 

similar to Hebertella except for ventral interior structures and its more convex pedicle valve. Small Hebertella specimens are indistinguishable from Plectorthis, 

and the two genera are obviously closely related 

(Schuchert and Cooper, 1932). 

Different species of Hebertella can be recognized on 

the basis of external morphology, espe~ially the pattern 

of costae and costellae and the outline and maximum 

size of the shell. Internal morphology remains relatively constant among the various species, with only 

minor differences due to increased secondary material 

in larger valves. The species of Hebertella herein described are H. frankfortensis Foerste, H. parksensis 

Foerste, and H. occidentalis Hall. Infraspecific variation is common in Hebertella, as determined from the 

large collections from single beds that were available 

for this study. Confident taxonomic decisions can be 

made on the basis of collections of about 10 or more individuals, but one or a few isolated specimens can be 

difficult to identify. There is no one consistent key feature that is reliable. Shells smaller than about 5 mm 

are generally unidentifiable. Features of specific importance, namely bifurcation of costae and spacing of 

costae, appear within 5 to 15 mm of beak. In general, 

one needs several specimens more than 10 mm long to 

make a confident identification. 

• 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND HETERORTHINA, ORDOVICIAN OF KENTUCKY M3 

Hebertella occidentalis shows the greatest amount 

of intraspecific variation. Particularly important is its 

relation to H. sinuata. Both of these species were defined by Hall (184 7), who noted the occurrence of the 

two together, including specimens intermediate between the typical forms. Foerste (1910) emphasized the 

apparent gradation. Similar observations were made 

in this study, and I consider all specimens that I have 

seen as belonging to a single variable species, H. occidentalis, the name having page priority (Hall, 184 7). 

Collections of Hebertella from Richmondian strata are 

few, and perhaps future work will show that the separation of a second species is valid within that stratigraphic interval. 

The collections studied do not include three species 

cited by earlier workers: H. alveata Foerste 1909; H. 

latasulcata Foerste 1914; and H. subjugata Hall 184 7. 

These are all listed as valid species by Sch uchert and 

Cooper (1932). I have seen the type specimens of these 

species. Hebertella alveata at the U.S. National Museum 

(USNM 78452, 87146, and 87158, a total of seven specimens) is characterized by a distinct and broad median 

depression on the brachial valve extending to the anterior margin; most specimens have alate cardinal extremities. Foerste (1909a) applied the name H. alveata 

richmondensis to similar forms having a less distinct 

median depression, narrower hingeline, and more convex brachial valve. He found this subspecies to be dominant over typical H. alveata at some horizons in beds 

of the Whitewater Formation. H. alveata occurs in the 

Liberty and Whitewater Formations of Ohio and Indiana. I consider H. alveata to be a distinct species, but 

none of the type specimens show interiors to confirm 

the generic identification. Collections in my study include only one sample from the Whitewater of Indiana, 

and this sample contains only H. occidentalis. 

Hebertella latasulcata (USNM 78707, two pedicle 

valves) was described as a mutation by Foerste (1914b) 

rather than as a distinct species in the modern sense. It 

has a broader shallower sulcus, a rather flat pedicle 

valve with a lower interarea, and a slightly more elongate muscle field. These characteristics are well within 

the range of variation of H. occidentalis, and H. latasulcata is thus not recognized as a valid species herein. 

Hebertella subjugata was described by Hall (184 7) 

as being similar to H. sinuata and H. occidentalis, its 

principal distinguishing character being much finer 

costellae. The five type specimens at the American 

Museum of Natural History (AMNH 1342/1) include 

three articulated specimens having definitely finer 

costellae, but also a fourth articulated shell having costellae like H. occidentalis. Hall (184 7, p. 130) noted 

that all three species, plus Plaesiomys subquadrata 

"are scarcely regarded as distinct, and are usually 

found mingled together in collections." In Hall and 

Clarke (1893), in which Hebertella was defined, H. subjugata was not included in the list of species belonging 

to Hebertella or in that belonging to any other genus. A 

question exists, therefore, as to the validity of this species, 

which could well be a variant within H. occidentalis. 

Hebertella frankfortensis Foerste, 1909 

Plate 4, figures 18--40 

Orthis frankfortensis James, 1871, p. 10 (nom. nud.) 

Hebertella frankfortensis Foerste, 1909b, p. 318-319, pl. 7, figs. 11a, b. 

Description.-Adult shell small for genus, rarely 

wider than 25 mm; outline transverse subelliptical to 

subround; cardinal extremities rounded, rarely a right 

angle or alate; ventral interarea curved and apsacline, 

dorsal interarea curved and apsacline, rarely orthocline. Low fold on brachial valve and shallow sulcus on 

pedicle valve in specimens longer than about 5 mm; 

fold and sulcus may be strongly developed on valves 

longer than 15 mm. Costae coarse, generally nonbranching, ranging in number from 29 to 40 in valves 

shorter than 10 mm and from 34 to 55 in valves longer 

than 10 mm, number not closely corresponding to size; 

with size increase, costae developing at hinge lateral to 

beak area; costae per 5 mm across midline, 8 to 12 at 

5 mm anterior to beak and 5 to 7 at 10 mm anterior to 

beak. 

Pedicle valve interior with pronounced muscle scars; 

adductors on double ridge, not enclosed by wide diductor 

scars. Length-width ratio of scar field ranges from 

about 1:1 to 1:5, increasing during ontogeny. 

Brachiophores bladelike, grooved on interior face, 

brachiophore supports converging to meet valve floor 

on either side of the cardinal process. Low notothyrial 

platform having prominent anterior edge. Curved fulcra! plates form floor of sockets. Cardinal process shaft 

thin, myophore usually crenulated, either small bulb 

or indistinguishable from shaft. Secondary thickening 

of cardinalia absent or minimum. Adductor muscle 

scars indistinguishable to faintly impressed on larger 

valves; all scars subelliptical, long axes oriented about 

30 o to midline. Low median ridge extending from notothyrial platform to between scars, faint ridge rarely 

present between the posterior margin and adductor 

scars. 

Ontogeny.-Small valves are distinctly transverse, 

with acute cardinal angles. The cardinal angles change 

from acute to about right angle in valves 2 to 3 mm 

long and then to obtuse in valves longer than 4 mm. 

The ventral interarea is relatively high, and the teeth 

are large. In the brachial valve, the cardinalia are also 

large with respect to size of valve. Growth was allometric when length of valve is compared with either 

(1) width of valve, (2) interarea height, (3) tooth size, or 

(4) cardinalia size. Length increased at a proportionately greater rate than any of these four features. 
M4 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

In pedicle valves 2 to 4 mm long, the beak is erect, 

interarea slightly curved and high with large delthyrium, teeth large; valve transverse. A thin veneer of 

secondary material exists in the muscle area; costae 

prominent everywhere else on interior of valve. In 

valves about 5 mm long, outline of diductor muscle 

marks becomes evident. Very faint adductor ridge may 

be present at this size, but it usually is not evident in 

valves shorter than 8 mm. Diductor muscle marks are 

generally distinct in specimens larger than 6 mm 

because of thickening of secondary deposits around 

muscle-attachment area. As growth proceeded, the attachment area moved anteriorly and, to a lesser 

degree, anterolaterally, so that the muscle markings 

became progressively more elongate. A thin veneer of 

secondary material was deposited circumferentially 

about the muscle area at a valve length of about 7 to 10 

mm, and the area of this veneer gradually enlarged 

during growth. This veneer may obscure the costae 

over an area as much as two-thirds of the valve length. 

As growth proceeded, addition of material took place at 

a greater rate at the anterior and anterolateral 

margins, so that the valve became less transverse. The 

development of the ventral sulcus is first evident in 

valves about 5 mm long by a distinct flattening of the 

anterior edge of the valve. A shallow depression may 

exist in valves 7 mm long. Thereafter, the development 

of the sulcus was variable. In some specimens, it remains a broad, very shallow depression; in others, it is 

an abrupt, relatively narrow depression. All variations 

within these extremes may exist within a collection 

from a single bed. 

In the brachial valve, the cardinal process was 

bladelike in early growth, and diductor muscles were 

attached on sides of the process. As growth proceeded, 

the cardinal process increased in length,. height, and 

slightly in width. The position of attachment of diductor muscles remained on the sides, in the more posterior 

part of the cardinal process. At a valve length of 4 to 

5 mm, the anterior half of the process had become rather 

bulbous, the posterior part (diductor-muscle area) remaining very narrow. By this growth stage, the valve 

curvature is such that the cylinderlike part of the process is directed almost ventrally, and the flat muscleattachment area is posterior to it. In valves larger than 

about 7 mm, the process has a cross section with the 

shape of a wide blade or a teardrop, both having crenulated sides. In the blade-shaped process, the bulbous 

part has been resorbed almost completely, and the 

muscle-attachment area has become enlarged. In the 

teardrop-shaped process, the bulbous part has been only 

partially resorbed. A bulbous process may be retained 

in valves as large as 15 mm. In larger valves, the front 

edge of the cardinal process extends anteroventrally, 

and a thin crenulated area of muscle attachment extends posteriorly to the valve floor. All variations in 

the cardinal process may be found in valves of all sizes 

in a collection from a single bed. Allometric growth existed in that all parts of the cardinalia are relatively 

large with respect to valve size in early growth as compared with later growth stages. 

A very thin notothyrial platform is present in valves 

2 mm long; it is thicker at the anterior edge, where a 

faint ridge of secondary material extends between the 

front edges of the brachiophore supports. As growth 

proceeded, this anterior edge became more prominent 

by being slightly thickened and by the impression of 

the posterior adductor muscles into it. In adult valves, 

the platform is thin and rather indistinct except for the 

anterior edge; the anterior edges of the brachiophore 

supports appear to curve sharply and converge to form 

the notothyrial platform. A medial ridge extends forward from the cardinal process area; it begins as a 

slight thickening in valves 3 to 5 mm long, and it may 

be prominent in adult valves where it extends to the 

anterior muscle marks. 

Each socket is floored by a concave fulcra! plate between the brachiophore and the hingeline. This plate 

was only slightly thickened during growth, and the 

space between it and the brachiophore support was not 

filled with secondary material to form a socket pad. 

Convexity of the brachial valve increased throughout growth; in valves longer than 15 mm, the brachiophores project almost directly anteriorly. The fold is 

discernible as a broad deflection in the anterior commissure when valve length is 5 to 7 mm. The deflection 

gradually increased in magnitude during growth, but 

the fold remained very broad and had no definite flanks. 

In a few specimens having a valve length of10 to 15 mm, 

the fold is narrower and slightly higher than the rest of 

the valve. Height of the fold is variable on larger 

specimens. 

The midline of the brachial valve is flattened or 

slightly depressed in most specimens. This flat area or 

depression disappears at a distance of 7 to 10 mm from 

the beak. Many brachial valves have no flattened midline. 

Discussion.-Infraspecific variation in H. frankfortensis can be seen in ventral muscle marks, branching 

of costae, and spacing of costae. The ratio of musclemark length to muscle-mark width in typical adult H. 

frankfortensis is about 1.3 to 1.4, with a maximum 

value of about 1.8. Some collections have an average 

muscle length-width ratio as great as 1.5, with a maximum of 2.4 for individual valves (as in USGS colin. 

4883-CO). 

N onbifurcating costae are typical of most specimens of H. frankfortensis, but in some collections as 

many as 25 percent of the larger valves have at least 

one branching costa. The branching costae may be on 
BRACHIOPOD GENERA HEBERT ELLA, DALMANELLA, AND. HETERORTHINA, ORDOVICIAN OF KENTUCKY M5 

either the sides of the valves or on the anterior part. 

Bifurcation rarely takes place within 8 mm of the beak, 

and commonly it is present only beyond 12 mm, so only 

relatively large valves will have costellae. The branching of costae may have been related to the sensory apparatus of these brachiopods. If, as in some modern 

species, a sensory seta was located in the mantle edge 

in a position corresponding to a costa, then, as growth 

proceeded, the valve margin was lengthened and the 

setae became more widely spaced. The production of 

new setae would have been of value for greater sensory 

perception, and the branching of costae would reflect 

the increase in setae. However, there was no critical 

spacing of costae beyond which bifurcation would take 

place, because most large valves have costae that are 

more widely spaced than in those valves having branching costae. 

The spacing of costae is also variable. Generally 9 

to 11 costae are present in a space of 5 mm, measured 

across the midline at a distance of 5 mm from the beak. 

In some collections, most specimens have 11 or 12 

costae per 5-mm interval. In any given collection in 

which most specimens have widely spaced costae, a few 

valves will have closely spaced costae. Similarly, closely 

spaced costae may be typical of a collection, but some 

valves will have widely spaced costae. 

Mature specimens of Hebertella frankfortensis are 

readily distinguished from H. parksensis and H. occidentalis. The latter two species have numerous bifurcating costae, and, in H. parksensis, the costae and 

costellae are closely spaced, as contrasted with the 

widely spaced, generally nonbifurcating costae of H. 

frankfortensis. Also, H. frankfortensis has a smaller 

maximum size (generally less than 20 mm long) and 

less pronounced fold and sulcus. Cardinal extremities 

of H. frankfortensis are rarely a right angle or alate, as 

is common in the other two species. In specimens 

smaller than abo:ut 4 mm, the three species cannot be 

confidently distinguished because the valves are too 

small for the characteristic features to have developed. 

Hebertella frankfortensis is possibly ancestral to H. 

occidentalis. Increased bifurcation of costae and an increase in size, accompanied by more pronounced development of fold and sinus, would have been the necessary 

evolutionary changes. However, there is no evidence 

for such evolution in collections from the study area. H. 

parksensis is unlikely to have descended from H. frankfortensis, considering the close packing of costellae and 

very early bifurcation of costae in H. parksensis. 

Foerste (1909b) identified specimens collected in 

Ohio by Meek (1873) as Hebertella frankfortensis. These 

specimens had been identified by Meek as H. borealis 

Billings. The species H. borealis Billings, from Chazyan 

strata in Quebec, was placed in Mimella by Cooper 

(1956). 

Stratigraphic distribution.-Hebertella frankfortensis ranges from the middle part of the Grier Limestone 

Member of the Lexington Limestone upward into the 

Millersburg Member of the Lexington in areas where 

the latter member is stratigraphically high (Franklin 

County). The species is abundant in the upper half of 

the Grier, and it is abundant in some beds at equivalent stratigraphic levels in other members. The lowest 

level at which collections of this species were made is 

about 100 ft below the top of the Grier in the Hunters 

Ferry Road section (Valley View Quadrangle), where 

the Grier is about 150 ft thick. USGS collection 

5098-CO was made from float, and, if it were near the 

in-place level, it would be the lowest collection. Otherwise, all collections were made no lower than the middle of the Grier. 

The species is abundant in the upper part of the 

Perryville Limestone Member of the Lexington Limestone, which is approximately equivalent to a stratigraphic level within the upper part of the Grier. It is 

present in the Sulphur Well, Brannon, and Tanglewood 

Limestone Members of the Lexington-Limestone, at 

levels below and above the Brannon Member. Where 

the Tanglewood is stratigraphically highest, in the 

Frankfort East and Switzer Quadrangles, H. frankfortensis is found in the lower part of the member. 

The highest level of collection of this species is in 

the Millersburg Member in the Midway Quadrangle, 

above the lower part of the Tanglewood Limestone 

Member. This collection, USGS 7790-CO, consists of 

typical H. frankfortensis but does contain an unusually 

large brachial valve, length 19 mm, width 25 mm. The 

species was not collected from the Millersburg at any 

other location or from other units (Tanglewood Limestone Member of the Lexington and Clays Ferry Formation) at equivalent stratigraphic levels. The absence 

of specimens may be due to biased collecting. 

No collections of H. frankfortensis were made from 

the lower part of the Clays Ferry Formation, but USGS 

collection 6909-CO is from the Point Pleasant Tongue 

of the Clays Ferry in the Falmouth Quadrangle, at a 

level approximately equivalent to the lower part of the 

Clays Ferry and uppermost part of the Grier or lower 

part of the Tanglewood Limestone Member of the Lexington. 

Two types of infraspecific variation may be of stratigraphic value, at least within the area of study-the 

spacing and bifurcation of costae. Specimens of H. 

frankfortensis that are stratigraphically low typically 

have more widely spaced costae, generally 9, 10, or 11 

costae per 5-mm interval, measured across the midline 

at 5 mm anterior to the beak. At a higher level are 

found specimens having more closely spaced costae, 

generally 11 or 12 per 5-mm interval. This level is in 

the uppermost part of the Grier Limestone Member 
M6 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

and several feet above the Grier, where the top of that 

unit is lower stratigraphically (as in the Salvisa Quadrangle). Similar specimens are found in the upper part 

of the Perryville Limestone Member, which is approximately at the same level. The closer spacing of the 

costae was not an evolutionary trend persistent in the 

area because H. frankfortensis specimens collected 

from still higher levels have the more widely spaced 

costae. 

Bifurcation of costae becomes more pronounced in 

specimens collected from the uppermost part of the 

Grier in some sections. As many as 25 percent of sufficiently large specimens may have one to four bifurcating costae. This feature is best seen in the Valley View 

Quadrangle, where such collections (USGS 4185-CO, 

4883-CO, 5096-CO) are found at the top of the Grier, a 

few feet above collections of specimens having the more 

closely spaced costae. In the Perryville Limestone Member, the highest collections (USGS 5016-CO, 6138-CO) 

contain specimens that have bifurcating costae but in 

lower proportion than those in the Valley View Quadrangle. These Perryville collections come from slightly 

higher levels than USGS 6915-CO and 6916-CO, 

which contain specimens having more closely spaced 

costae. The persistence of bifurcating costae at this 

general stratigraphic level is questionable because, in 

the Salvisa Quadrangle, the collections that span the 

upper part of the Grier and lower part of the Tanglewood contain only rare specimens that have bifurcating costae. Whether this variation is of evolutionary 

significance is difficult to test, because collections of 

this species above the Grier have few specimens of sufficient size. These collections would be expected to contain a higher proportion of valves having bifurcating 

costae, but this expectation is not confirmed by the 

available specimens. The highest collection of H. frankfortensis, USGS 7790-CO, from the Millersburg Member in the Midway Quadrangle, includes seven large 

valves, only one of which has a single bifurcating costa. 

Hebertella occidentalis (Hall), 1847 

Plate 5, figures 18-41 

Orthis occidentalis Hall, 184 7, p. 127-128, pl. 32a, figs. 2a-m, pl. 

32b, figs. 1a-i. 

Orthis sinuata Hall, 1847, p. 128-129, pl. 32b, figs. 2a-k, pl. 32c, 

figs. 21-s. 

Orthis subjugata Hall, 1847, p. 129-130, pl. 32c, figs. 1a-n. 

Hebertella latasulcata Foerste, 1914b, p. 131, pl. 3, figs. 7a, b. 

Description.-Adult shell medium to large size, 

length generally 20 to 35 mm, width 25 to 40 mm. Cardinal extremities rounded to alate. Costae branching 

extensively, some branching originating within 6 mm 

of beak, most about 8 mm or more away from beak. 

Seven to 10 costae and costellae per 5 mm, counted 

across the midline, at 5 and 10 mm anterior to beak. 

Costellae are narrow near point of bifurcation, some 

enlarging to width of primary costae, others remaining 

narrower; no pattern to costellae size observed. A way 

from points of branching, intercostal spaces range in 

size from less than to greater than width of costellae. 

Costae are more widely spaced near midline of valve 

than on flanks because branching near midline begins 

farther from beak; wider spacing especially conspicuous 

within 10 to 15 mm of beak. 

Pedicle-valve beak generally suberect with a slightly 

curved (orthocline) interarea. Lateral profile, gently 

convex near beak and flat to slightly concave toward 

anterior margin; valves having erect beaks may be concave from near beak area to anterior margin. Sulcus 

deep, originating about 7 to 10 mm fr<;>m beak, rarely 

within 5 mm of erect beaks. Sulcus narrow, becoming 

deeper as valve grows, at lengths of 20 to 25 mm tending to deepen abruptly, causing sharp deflection in the 

anterior edge of valve. Rim of muscle marks thick; adductor double ridge prominent, elevated above diductor 

marks. Secondary thickening of valve common in 

larger specimens. 

Brachial valve interarea strongly curved, apsacline. 

Cardinal process consisting of rodlike anterior part 

and bladelike posterior connection to floor of valve; tip 

of cardinal process rarely swollen. Adductor muscle field 

slightly discernible; low narrow median ridge extending to about one-third valve length; rarely, faint ridge 

between anterior and posterior scars; peripheral ridge 

absent. Fold beginning about 8 to 10 mm from beak, remaining narrow but relatively low as length increases. 

In some specimens larger than 20 mm, sharp deflections mark margins of fold, but crest of fold remains 

rounded; these individuals have exaggerated narrow 

sulcus in pedicle valve. Some specimens have narrow 

depression or flat area in midline of umbonal region; 

umbo remains smoothly convex in most specimens. 

Distinguishing characteristics.-The branching 

costae and more prominent sulcus and fold distinguish 

H. occidentalis from H. frankfortensis, except in specimens too small for branching costae and development 

of the sulcus (shorter than about 5 mm). The coarser, 

more widely spaced costae and less erect beak of H. 

occidentalis make it distinctive from H. parksensis. 

Some variant specimens of H. occidentalis are indistinguishable from variant H. parksensis. Maximum size 

of H. occidentalis (as wide as 45 mm) is greater than 

that of H. frankfortensis and H. parksensis. 

Ontogeny.-The development of specimens of H. occidentalis is similar to that of H. frankfortensis except 

for the specific characteristics. To a length of 5 to 8 mm, 

the species are indistinguishable; beyond that length, 

the costae of H. occidentalis bifurcate, and the sulcus is 

more pronounced. Also, in small pedicle valves, the 

beak of H. occidentalis is higher. 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND HETERORTHINA, ORDOVICIAN OF KENTUCKY M7 

Mter a valve length of 10 to 15 mm is reached, secondary material is added to the pedicle-valve interior. 

In large valves, the internal thickening is very pronounced, and the muscle marks deeply imbedded. Very 

little thickening of cardinalia or the floor of the 

brachial valve takes place. 

Discussion.-Hebertella occidentalis and H. sinuata 

are herein regarded as synonyms. Hall (184 7) recognized the species Orthis occidentalis and 0. sinuata 

from the Upper Ordovician of the Ohio Valley region. 

Orthis sinuata was used as the type species of Hebertella as defined by Hall and Clarke (1893). The two taxa 

have always been recognized as being similar, and Hall 

(184 7, p. 130) said that they (along with H. subjugata) 

u are usually found mingled together in collections." 

Meek (1873) stated that the two species are connected by 

intermediate forms and, thus, probably represent only 

varieties of the same species. Cumings (1908, p. 907) 

found that there was a ~~perfectly graded series of intermediate forms" between the two taxa, and he considered H. sinuata to be a variety of H. occidentalis. He 

reported that H. occidentalis var. sinuata ranged from 

the Lorraine Shale (Edenian-Maysvillian) into the 

Liberty Formation (upper Richmondian) and was present also in the Elkhorn Formation (uppermost Richmondian); H. occidentalis was found in the upper part 

of the Liberty and the Whitewater Formations (upper 

Richmondian). Foerste (1910, p. 53) considered the two 

to be separate species, although he noted that ~~at the 

same locality all the intermediate stages are almost 

certain to be found." Schuchert and Cooper (1932) 

listed H. occidentalis and H. occidentalis sinuata 

among species of Hebertella. Later, Howe (1966) found 

that considerable overlap existed in the supposedly 

diagnostic features of H. occidentalis and H. sinuta, on 

the basis of his study of large collections in the U.S. 

National Museum. 

My investigation of large collections also showed 

that intermediate forms exist between utypical" H. 

occidentalis and H. sinuata and that all types may occur together. The two features generally used to distinguish the taxa are (1) a median depression in the umbonal region of the brachial valve of H. occidentalis 

and (2) the coarser, more widely spaced costae of H. 

sinuata. Any large collection is likely to contain some 

brachial valves that have a median depression and 

some that do not; the coarseness and spacing of costae 

is not consistent with either type of valve. The conclusion is that we are dealing with one variable species 

and that it should bear the name Hebertella occidentalis, which has page priority. Perhaps a study of 

Richmondian specimens in Ohio and Indiana would 

show that a subspecies H. occidentalis sinuata could be 

consistently recognized. I have seen three large 

Richmondian collections from Indiana, but they consist 

of the variable H. occidentalis as found in Kentucky. 

Hebertella subjugata (Hall) 184 7 is also probably a 

variant morphologic type within H. occidentalis. Hall 

(184 7) gave H. subjugata several distinguishing characteristics, the main one being much finer costae than 

those of H. occidentalis. However, all these features 

can be found in variable H. occidentalis. Of the five 

type specimens of H. subjugata (AMNH. 1342/1), three 

specimens do have fine costae and costellae, as in H. 

parksensis. The other two specimens have coarse costae, 

as in H. occidentalis. I have seen some specimens that 

have fine costae in large collections of H. occidentalis, 

and I think that all Hall's specimens do fall within the 

range of variation of that species. As stated above, Hall 

usually found H. subjugata together with H. occidentalis and H. sinuata. Three USGS collections (7319-CO, 

7321-CO, 7322-CO) from the Millersburg Member of 

the Lexington Limestone in the Winchester Quadrangle 

(Maple Street Section) include specimens that have 

fine costae. Although they are similar to H. subjugata, 

I consider them to be variant H. occidentalis. 

Perhaps Hall and Clarke (1893) did not consider H. 

subjugata to be a valid species because they did not list 

it with other Hebertella species. Also, a catalog of 

AMNH type specimens (Whitfield .and Hovey, 1898) 

listed the five type specimens as H. occidentalis, with 

the remarks uas types of Orthis subjugata." 

Stratigraphic distribution.-The collection (USGS 

D-1172-CO) containing the oldest H. occidentalis was 

found in the Clays Ferry Formation in the Ford Quadrangle, about 25 ft above the Tanglewood Limestone 

Member of the Lexington Limestone. This part of the 

Clays Ferry intertongues with the Millersburg Member of the Lexington and the upper tongue of the 

Tanglewood, and the level of collection is perhaps 

slightly lower than that of H. occidentalis collections 

from the Millersburg in adjacent quadrangles. The 

lowermost Millersburg H. occidentalis is found about 

10ft below the Strodes Creek Member of the Lexington, a persistent unit that extends north from the Winchester Quadrangle. 

Considering the uncertainty of correlation based on 

mapping, the lower part of the range of H. occidentalis 

may overlap with the upper range of H. parksensis. 

However, in any given section where the two species 

are present, H. occidentalis always is found above H. 

parksensis. USGS collection D-1172-CO does contain 

one finely costellate pedicle valve that could be H. 

parksensis. Nowhere else were the two species found 

together. 

The lowest level of H. occidentalis is approximately 

equivalent to the highest level of H. frankfortensis 

(USGS colin. 7790-CO) from the Millersburg Member 

in the Midway Quadrangle. An unusual occurrence of 

two apparent H. occidentalis brachial valves is in 
M8 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

USGS collection 6138-CO, which contains scores of H. 

frankfortensis specimens. These are from the Perryville Limestone Member of the Lexington Limestone in 

the Bryantsville Quadrangle. This unit is much lower 

than the lowest known H. occidentalis, in the Ford 

Quadrangle, and large collections in intervening 

strata contain only H. frankfortensis or H. parksensis. 

Possibly the valves are very aberrant H. frankfortensis 

specimens, although they are quite distinct and are 

like most H. occidentalis specimens. An unlikely 

explanation is that the sample was contaminated. 

Finally, these valves may be true H. occidentalis that 

occur much lower than other known H. occidentalis. 

Hebertella occidentalis is present in all the formations that overlie the Lexington Limestone, from Edenian to Richmondian strata. It is common to abundant 

in most of this stratigraphic interval. The youngest collections come from the Preachersville Member of the 

Drakes Formation in the Hedges Quadrangle in central 

Kentucky. In northern Kentucky where the Preachersville Member is present, the highest collections are 

from the upper part of the Bull Fork Formation, about 

20 ft below the Preachersville. The collections made 

from Richmondian rocks in Indiana and Ohio (USGS 

6139-CO to 6141-CO, 7833-CO, 7834-CO) are probably about the same age as the highest collections in 

northern Kentucky. 

Despite the long stratigraphic range of the species, 

no evolutionary trends or consistent morphologic differences from level to level were found. Variations 

within the species appear to have no correlation with 

stratigraphy. 

Hebertella parksensis Foerste, 1909 

Plate 5, figures 1-17 

Herbertella maria-parksensis Foerste, 1909b, p. 319, pl. 7, figs. 6a, b. 

Description.-Adult shell medium sized for genus, 

generally 15 to 25 mm long and 10 to 33 mm wide. Cardinal extremities rounded to alate. Costae bifurcate extensively, branching originating mainly beyond 4 mm 

from beak. Usually 11 to 13 (maximum 17) costae and 

costellae per 5 mm, counted across the midline, at 5 

and 10 mm anterior to beak. Costellae uniform in size 

and generally closely spaced, especially within 10 mm 

of beak. 

Pedicle-valve beak generally suberect with slightly 

curved interarea; beak erect with flat orthocline interarea in a minority of valves. Valve gently convex 

near beak and almost flat toward anterior margin; 

beak erect in nearly flat valves. Sulcus conspicuous, 

originating about 4 to 7 mm from suberect beaks, 

within 3 mm of erect beaks. Narrow sulcus becoming 

deeper as valve grows; anterior edge of valve commonly sharply deflected in specimens longer than 10 mm; 

sulcus shallow in some adult specimens. Interior of 

valve has pronounced muscle marks with elevated rim 

so that many specimens have almost a muscle platform; adductor double ridge well elevated above diductor marks; radiating ridges and grooves may be present in diductor marks. 

Brachial valve interarea strongly curved, apsacline; 

notothyrium large. Adductor muscle field slightly discernible; median ridge generally very low and narrow; 

rarely, a faint ridge between anterior and posterior 

scars; no peripheral ridge. Brachial valve fold originating beyond 8 mm from beak; generally narrow and low, 

although sharp deflection may exist in anterior edge of 

valve and corresponding sulcus may be deep. 

Ontogeny.-The growth of specimens of H. parksensis was similar to that of specimens of H. frankfortensis 

except for the specific characteristics. Costae are more 

closely crowded in the beak area, and costellae appear 

as near as 3 to 6 mm from the beak. Ventral sulcus first 

appears at 3 to 7 mm from the beak and commonly is a 

sharp deflection in valves 10 to 15 mm long. When a 

valve length of 8 to 10 mm was reached, the rim 

around the ventral muscle rapidly developed, so that 

the rim rises well above the valve floor in valves more 

than 10 mm long. · 

Distinguishing characteristics.-The closely spaced 

costae and costellae are the most reliable character. 

For any given size valve, the sulcus of H. parksensis is 

generally more pronounced than those in H. frankfortensis and H. occidentalis and the ventral musclemark rim is more pronounced; the muscle marks may 

even be elevated in H. parksensis. 

Discussion.-Foerste (1909b) originally used the 

name H. maria-parksensis, but he considered it to be a 

distinct species, and in the same article and in later 

publications he referred to the species as H. parksensis. 

Bassler (1915) and Schuchert and Cooper (1932) continued usage of H. maria-parkensis [sic]. I consider H. 

parksensis to be more appropriate because it fits the 

rules of zoological nomenclature for a distinct species. 

The spelling H. parksensis is correct, as the name is 

derived from Parks Hill, Ky., although the spelling H. 

parkensis has commonly been used. 

Hebertella parksensis from Kentucky and H. maria 

(Billings), from Richmondian strata on Anticosti Island, southeastern Canada, are indeed similar. Foerste 

(1909b, p. 319) based his comparison on figured specimens of H. maria and stated that H. parksensis is larger 

and the pedicle valve is umuch more convex toward the 

beak." I have examined the type specimens of H. maria 

belonging to the Geological Survey of Canada (syntypes: GSC 2271, 2271a, 2271b, 2271c; hypotypes: GSC 

29599, 29618; also two nontype specimens). Most are 

smaller than typical H. parksensis, but one is large (18 

mm long, 23 mm wide). Pedicle-valve convexity is 

slightly less in H. maria. The lateral edges and cardinal 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND HETERORTHINA, ORDOVICIAN OF KENTUCKY M9 

extremities of H. maria valves are distinctly rounded, 

whereas, in any collection of H. parksensis, many valves 

will have straight lateral edges and even alate cardinal 

extremities, in addition to valves having rounded lateral edges. Spacing and bifurcation of costae and costellae are similar, except for specimen GSC 2271 b, 

which has more widely spaced and fewer branching 

costae. Other external characteristics are similar. All 

the reference specimens of H. maria are articulated, so 

no internal features are known. Larger collections of 

H. maria should be examined before judgment is passed 

on the significance of the differences cited. 

Stratigraphic distribution.-Hebertella parksensis 

seems to be confined to the upper part of the Lexington 

Limestone and to parts of the Clays Ferry Formation 

and the Point Pleasant Tongue of that unit that are 

stratigraphically equivalent to the upper part of the 

Lexington. The lowest collection, USGS 7792-CO, is 

from the top of the Grier Limestone Member of the Lexington in the Ford Quadrangle; no other collections 

come from the Grier. USGS collection 6146-CO comes 

from the Point Pleasant Tongue in the Felicity Quadrangle, Clermont County, Ohio. The Point Pleasant is 

equivalent to the lower part of the Clays Ferry in central Kentucky (Cressman and Karklins, 1970). 

All 23 other collections of H. parksensis come from 

a stratigraphic interval about 30 ft thick. This interval 

spans part of the lower and the whole middle part of 

the Millersburg Member of the Lexington and the interbedded lower and upper tongues of the Clays Ferry 

Formation, as these are exposed in the more eastern 

quadrangles (Cynthiana Quadrangle south to Winchester Quadrangle, also Sadieville Quadrangle). A regional 

facies framework diagram was given by Black and 

Cuppels (1973). The highest level of collection is apparently the upper tongue of the Clays Ferry, from 

which USGS 6143-CO was obtained in the Cynthiana 

Quadrangle. The Strodes Creek Member of the Lexington is a stratigraphic marker from the Cynthiana to 

the Winchester Quadrangles (Black and Cuppels, 

1973). The highest H. parksensis occurs about 14 to 20 

ft below the Strodes Creek (example is USGS colln. 

7333-CO in Strodes Creek type section). Hebertella occidentalis is found between the highest H. parksensis 

and the Strodes Creek, as well as higher in the section. 

No collections of H. parksensis come from the Tanglewood Limestone Member of the Lexington, which 

intertongues with the Millersburg and Clays Ferry 

and which also underlies the Millersburg. Silicification 

is very limited in the Tanglewood; probably the 

restricted distribution of collections of H. parksensis is 

due to collecting bias. 

The oldest H. parksensis is found in the top of the 

Grier Limestone Member, so the stratigraphic ranges 

of this species and H. frankfortensis overlap, although 

the two species are rarely found together. USGS collection 6143-CO, probably the youngest of H. parksensis, 

contains three H. frankfortensis valves. This is approximately the same stratigraphic level as USGS 7790-CO, 

the highest H. frankfortensis, from the Millersburg 

Member in the Midway Quadrangle. Several other collections of H. parksensis contain possible H. frankfortensis, but the differentiation of young specimens of H. 

frankfortensis from those of Plectorthis is very difficult. 

Superfamily ENTELETACEA Waagen 

Family DALMANELLIDAE Schuchert 

The analysis of dalmanellids by Williams and 

Wright (1963) is the basis for the taxonomy used in this 

report. Neuman (1967) used the same basis in a study 

of some of the taxa described herein. Before Williams 

and Wright's article, the taxonomy of dalmanellids 

was confusing and unsatisfactory, principally because 

of the considerable infraspecific variation characteristics of dalmanellids. Some investigators chose such 

variable features as characters for discrimination of 

genera and species. 

Genus DALMANELLA Hall and Clark, 1892 

Type species.-Orthis testudinaria Dalman, 1828, p. 

115, by original designation. 

. Description.-Outline subcircular to transversely 

subelliptical to subrectangular; profile ventribiconvex 

to almost planoconvex; variably developed dorsal 

sulcus. Coarsely to finely fascicostellate, costae and 

costellae on lateral slopes are curved; median costa 

present in dorsal valve of some species; prominent 

growth lines variably developed, irregularly spaced 

where present, minute growth lines (fila) between 

costellae are present in some species. Maximum length 

20 to 25 mm, maximum width 25 to 30 mm, maximum 

convexity about 8 mm. Ventral muscle field cordate to 

bilobed, submedian diductor lobes usually extending 

beyond adductor, generally confined to posterior half of 

valve; posterolateral edges of field bounded by small 

ridges extending from dental plates; length and width 

of field quite variable. Cardinal process bilobed, undifferentiated, commonly thickened with secondary material; shaft rising from notothyrial platform merging 

with median ridge extending to about midlength of 

valve. Brachiophore bases either convergent onto 

median ridge or subparallel down to edges of ridge; secondary thickening around b~achiophore bases. Tiny 

rodlike brachiophore processes, rarely preserved, extend from tips of brachiophores, length about one-third 

to one-half that of brachiophores; processes curving 

anteriorly from tip of brachiophores. Dorsal adductor 
M10 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

field quadripartite, elongately suboval, may extend to 

midlength; posterior edge may be imbedded in secondary material around cardinalia and median ridge. 

Secondary deposits in valve interiors range from nil to 

relatively thick, with imbedded muscle marks; thickening generally less in ventral valve. 

Discussion.-Dalmanella was recognized principally on the basis of the cardinalia that are different 

from those of Heterorthina, the only other dalmanellid 

found in this study. The name Onniella has been used 

by other workers (Cooper, 1956; Hall, 1962) for species 

placed in Dalmanella in this report, but, according to 

Williams and Wright (1963), that genus has brachiophore bases that diverge toward the valve floor. No 

Kentucky specimens show such features, except for 

Heterorthina, which is otherwise different from 

Onniella. 

Variation in the cardinalia is produced by secondary deposits that form brachiophore bases (supports), 

ancillary struts, and thickening around the cardinal 

process. The brachiophores are bladelike structures, 

subtrigonal in side view, that stand erect and are 

directed anteroventrally. In very young specimens, the 

outer faces of the brachiophores formed the inner edges 

of the sockets. As the individual grew, deposits were 

added to the dorsal edges and lower inner faces of the 

brachiophores to form the brachiophore bases (supports) and ancillary struts. In Dalmanella, the brachiophore bases are (1) convergent to the median ridge, 

which extends forward from the notothyrial platform, 

or (2) they extend straight down to the valve floor and 

thus are subparallel. In (2), secondary deposits connect 

the inner faces of the brachiophore bases and the 

median ridge. Gradations between (1) and (2) can be 

found within a single species, but most specimens of 

one species will have either distinctly convergent or 

subparallel brachiophore bases. The presence of fulcra! 

plates is likewise variable within a species, but plates 

are far more prevalent in species that have convergent 

brachiophore bases. 

Dalmanella sulcata and D. bassleri have convergent 

brachiophore bases. In both species, the brachiophores 

and bases in very small specimens are subparallel, and 

they bound the sockets. As the individuals grew, more 

material was added to the dorsal edges in an anteromedian direction, so that the main supports of the 

brachiophores are convergent to the median ridge. In 

D. sulcata, material was also added in an anterolateral 

direction, so that a wall-like structure extended forward and continued to bound the sockets. The outer 

face of this structure may be inclined toward the hingeline, and, in some specimens, the lower part of the 

structure is slightly curved outward. Generally, this 

structure merges into the valve, the socket being aqjacent. In some specimens, distinct fulcra! plates are 

present; the space between them and the valve floor 

may be filled with secondary deposits to form a socket 

pad. The support joining the median ridge extends farther forward than the structure that bounds the socket, 

and this support forms the ceiling of a cavity that 

forms between the two structures and the valve floor; 

this cavity is filled with secondary deposits in some 

adults. In D. bassleri, distinct curved fulcra! plates 

bound and floor the sockets; part of the cavity beneath 

the fulcra! plate may be filled with secondary material 

to form a socket pad. 

The development of brachiophore supports in D. 

sulcata is significant when compared with that of 

Heterorthina macfarlani. In H. macfarlani, the original 

brachiophore and base structure is similar to that of D. 

sulcata. However, as growth proceeded, the main 

development of the bases was in an anterolateral direction, and these structures continued to bound the 

sockets; thus, the main brachiophore supports are thick 

bladelike structures that slope slightly posteriorly 

and so are divergent in a dorsal direction. Also, secondary material was added at a slower rate between 

the lower inner face of the brachiophore supports and 

the median ridge to form ancillary struts, which are 

analogous to the main brachiophore supports in 

Dalmanella sulcata. A cavity formed ·between the 

struts, the brachiophore supports, and the floor of the 

valve; in adults, this cavity may be filled. 

Subparallel brachiophore supports are characteristic of Dalmanella fertilis, D. multisecta, and D. meeki. 

Commonly, massive secondary deposits (ancillary 

struts?) join the brachiophore bases and the median 

ridge, and fulcra! plates are rare because the brachiophore bases bound the sockets. Therefore, unlike cardinalia development in D. sulcata and D. bassleri, the 

main growth of the brachiophore bases was in an anterolateral direction, and the secondary material between the bases and the median ridge is not the main 

support of the brachiophores. A cavity is never found 

under the brachiophore supports, rather a buttress 

above the posterior edges of the muscle marks. 

Secondary thickening of the cardinal process, especially the shaft, takes place in all species of Dalmanella. 

In some species, extensive thickening is confined to 

relatively few large specimens, as in D. sulcata and D. 

bassleri, but, in other species, it started early and can 

form a large mass between the brachiophores, as in D. 

meeki. 

The ventral musculature can also be quite variable 

within a single species of Dalmanella. The outline of 

the muscle field ranges from cordate, where the diductor marks are only slightly longer than the adductors, 

to elongate bilobed, where the diductor marks extend 

well beyond the adductor marks but do not enclose 

them. 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND HETERORTHINA, ORDOVICIAN OF KENTUCKY M11 

Dalmanella bassleri Foerste, 1909 

Plate 2, figures 15-28 

Dalmanella bassleri Foerste, 1909a, p. 215-216. 

Onniella bassleri (Foerste), Hall, 1962, p. 144-145, pl. 20, figs. 41, 42. 

Dalmanella bassleri Foerste, Neuman, 1967, p. 6, figs. 35-44. 

Diagnosis.-Large size for genus, as much as 22 

mm long and 27 mm wide, subrectangular to transversely subelliptical, valves becoming more subelliptical as they grow; ventral valve subcarinate, medium 

convex, 4 or 5 mm depth in largest specimens; dorsal 

valve almost flat to slightly convex, as much as 2 mm 

in depth; both valves more convex in early growth 

stages, become flatter as they grow; distinct dorsal 

sulcus present in small to medium specimens, shallowing and disappearing anteriorly in large specimens; 

both valves thin compared with other Dalmanella 

species. Six to 9 costae and costellae, rarely 10, within 

2-mm interval measured 5 mm anterior to dorsal umbo. 

Prominent growth lines generally not present; fila 

absent. Ventral muscle field cordate to bilobed, relatively widely splayed in some specimens, generally 

confined to posterior one-third of valve. Cardinalia 

relatively small compared with valve size, especially in 

large specimens; brachiophore bases convergent to 

median ridge, fulcra! plates present in small to large 

specimens, socket pad may form by secondary deposits 

in large valves; secondary deposits thicken cardinal 

process and brachiophore bases in some large specimens. Dorsal adductor muscle marks generally poorly 

defined except in some larger specimens; very little 

secondary thickening of valve floor. 

Discussion.-The most diagriostic features are the 

large size, low convexity, small cardinalia with convergent brachiophore supports and with fulcra! plates, 

and distinctly thin valves and delicate appearance of 

most specimens. The cardinalia are similar to those of 

Dalmanella sulcata but are relatively larger in D. 

sulcata and generally lack fulcra! plates; D. sulcata is 

smaller in overall size. Specimens of D. bassleri, which 

have flatter dorsal valves, are similar externally to 

Heterorthina macfarlani, but the cardinalia are different. 

Type specimens and others identified by Foerste 

were described by Neuman (1967), who did not have 

the collections of specimens used in my study. Foerste's 

specimens came from the ucynthiana Formation" adjacent to the Ohio River. Hall (1962) described a small 

number of specimens from the overlying Edenian 

uFulton" beds in the Cincinnati area. The species also 

occurs in the basal part of the Martinsburg Formation 

in southwest Virginia (Walker, 1967, identified as D. 

cf. bassleri). 

Stratigraphic distribution.-Collections of Dalmanella bassleri are few. The species is apparently confined to the stratigraphic interval that contains the 

Point Pleasant Tongue of the Clays Ferry Formation, 

the lower part of the Kope Formation, and equivalent 

parts of the main body of the Clays Ferry Formation 

and the Lexington Limestone (above the Grier Limestone Member). USGS collection 6909-CO is from the 

lower 20 ft of the Point Pleasant Tongue, and collection 

7824-CO is from the upper 25 ft of that unit. The Point 

Pleasant corresponds to the strata of the so-called Cynthiana Formation from which Foerste (1909a) collected 

his specimens. Probable D. bassleri are found in the 

Kope Formation (USGS colin. 6910-CO) about 66 ft 

above the Point Pleasant; the lower part of the Kope 

corresponds to Hall's (1962) uFulton" beds. The species 

was questionably identified in the lower part of the 

Tanglewood Limestone Member of the Lexington 

Limestone in the Monterey Quadrangle (USGS colin. 

7823-CO), at a level approximately equivalent to 

lower middle parts of the Point Pleasant Tongue. The 

relatively few collections from the upper part of the 

Lexington Limestone and the Clays Ferry Formation 

may account for the apparent scarcity of D. bassleri in 

these units. 

Dalmanella fertilis (Ulrich) 1909 

Plate 1, figures 1-24 

Orthis (Dalmanella) fertilis Ulrich in Bassler, 1909, p. 182, pl. 24, 

fig. 5. 

Onniella fertilis (Ulrich) Cooper, 1956, p. 954-955, pl. 157, figs. 1-3; 

pl. 157, figs. 5, 6; pl. 159, figs. 21-37. 

Description.-Medium size, length generally less 

than 16 mm; subcircular to slightly transverse outline; 

cardinal extremities generally rounded; ventral valve 

has low to medium convexity, subcarinate to gently 

rounded in posterior view; dorsal valve almost flat, dorsal sulcus present in some specimens. Seven or 8 costae 

and costellae, rarely 6 in 2-mm interval measured 5 

mm anterior to dorsal umbo. Prominent growth lines 

present or absent, fila present. Ventral muscle field 

cordate to bilobed, generally no longer than one-third 

of valve, rarely extending to midlength and beyond. 

Brachiophore bases may form buttresses above 

posterior adductor marks; thick socket pads may be 

present, distinct fulcra! plates occurring only in some 

young specimens; thickening of cardinal process 

variable; adductor muscle marks impressed in secondary material, commonly thickening valve interior. 

Discussion.-The best features for identification 

are the cardinalia, although the subcircular, flat, generally nonsulcate dorsal valve is usually a reliable 

guide. 

Dalmanella fertilis is widespread in Middle Ordovician rocks in the Eastern United States. I have seen 

collections of James Hall's "Dalmanella testudinaria" 

from the Trenton Group of New York, which include 

specimens used in descriptions and figures in the 
M12 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

uPaleontology of New York," volumes 1 and 8: the collections from Lowville, N.Y. (AMNH 690/3), consist of 

D. fertilis. Specimens used for the drawings in volume 

8, plate 5B, figures 38 and 39 are in these collections. 

The collections from Middleville, N.Y. (AMNH 690/1), 

probably include different species. A slab bearing this 

collection number has on it specimens of D. fertilis, and 

a pedicle valve interior was used for figure 38, plate 

5B, in volume 1. 

Stratigraphic distribution.-Dalmanella fertilis is 

common to abundant throughout the Curdsville Limestone Member of the Lexington Limestone. The species 

was not collected from any other unit, with the possible 

exception of USGS collection 4124-CO, which was 

made early in the collecting program and which was 

thought to be from the Lagana Member of the Lexington Limestone. 

Dalmanella meeki (Miller) 1875 

Plate 3, figures 20-30 

Orthis emacerata Hall (partim) Meek, 1873, p. 109, figs, la-c, 2a-g. 

Orthis meeki Miller, 1875, p. 20. 

Dalmanella meeki (Miller), Foerste, 1909a, p. 218, pl. 4, figs. 16a, b. 

Onniella meeki (Miller), Hall, 1962, p. 145-148, pl. 19, figs. 1-24, pl. 

20, figs. 1-10. 

Description.-Like Dalmanella multisecta, except 

for the following: medium to large size, generally less 

than 18 mm long, 22 mm wide; outline subcircular to 

transverse. Dorsal valve commonly more convex and 

sulcate. Cardinalia extremely thickened in mature 

specimens, cardinal process greatly inflated and filling 

space between brachiophore bases. 

Discussion.-My study was based on only six collections, totaling 39 specimens, most of which showed 

only exteriors. Hall (1962) gave a description and many 

illustrations based on a large number of specimens. He 

provid~.d a co:g.tplete synonomy .and a review of the complex nomenclatural history of the species. 

As discussed under Dalmanella multisecta, that 

species and D. meeki are similar. Definite distinction 

generally can be made only if collections happen to include specimens larger than about 14 mm, with very 

thickened card~nalia, or transverse specimens of D. 

meeki. Foerste (1909a, p. 219) quoted Miller (1875, 

p. 23) that (1) D. multisecta was found as high as 250 ft 

above low-water mark at Cincinnati, Ohio (in the 

nFairmount"), and D. meeki was found from that level 

upward and (2) ((It would be impossible to determine 

where one form begins and the other ends, as they 

clearly intermingle, and leave the constantly recurring 

impression that they are not specifically distinct." 

Stratigraphic distribution.-Collections of D. meeki 

used herein come from the Bull Fork Formation, 23 to 

111 ft above the base of the unit, at the County Line 

Section in the Orangeburg and Maysville East Quad- -

rangles. The Bull Fork is mainly Richmondian in age 

(Peck, 1966), and the collections would correspond to 

Hall's (1962) designation of D. meeki as being of 

Richmondian Age. However, earlier workers, including 

Foerste (1909a), thought that D. meeki occurred as low 

as the ((Fairmount" (equivalent to part of the Fairview 

Formation of Peck, 1966), which is Maysvillian in age. 

Hall (1962) gave the range of D. multisecta as EdenianMaysvillian and that of D. meeki as Richmondian, 

without discussing the reasons for his disagreement 

with earlier workers. Only a thorough study of taxonomy and stratigraphic distribution based on many 

collections can resolve the problem. 

Dalmanella multisecta (Meek), 1873 

Plate 3, figures 1-19 

Orthis multisecta James, 1871, p. 10 (nomen nudum). 

Orthis emacerata var. multisecta Meek, 1873, p. 112, pl. 8, fig. 3. 

Orthis multisecta James, Miller, 1875, p. 22. 

Onniella multisecta (Meek) Hall, 1962, p. 148-150, pl. 20, figs. 11-13. 

Description.-Small to medium size, generally less 

than 14 mm long; outline commonly subcircular, may 

be transversely subelliptical, especially in smaller 

specimens. Ventral valve subcarinate with medium 

convexity for its size, as deep as 3 mm. Dorsal valve 

slightly convex to almost flat in larger specimens; 

distinct dorsal sulcus present, shallowing anteriorly 

and may be indistinct at front margins of some larger 

valves. Median costa present on dorsal valve; 6 to 9 

costae and costellae, but generally 7 to 8, per 2 mm, 

measured 5 mm anterior to dorsal umbo; fila present. 

Ventral valve teeth large; muscle field generally 

distinctly bilobed with wide adductor track, length 

about one-third valve length, width variable; thickening of valve interior common, hence muscle field generally impressed, pallial markings may be faintly visible. 

Stout brachiophore bases subparallel to valve floor 

slightly convergent in early growth; in mature specimens, the bases curving laterally, as seen in plan view; 

bases thickened with secondary material, especially on 

inner faces, forming buttress above posterior muscle 

marks. Bases bound inner side of wide sockets; thick 

socket pads develop in early growth. Cardinal process 

shaft thin in small valves, flat and wide in medium to 

large valves because of secondary thickening, furrows 

present in either side of widened shaft; myophore hilobed, sessile, prominent but not excessively enlarged 

as other parts of cardinalia. Adductor muscle marks 

generally well defined, posterior marks deeply impressed in secondary material around cardinalia; outline of each muscle mark smooth, posterior marks subtrigonal; outline of field transversely subcircular; 

anterior margin of field generally at midlength of 

valve or slightly beyond. 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND HETERORTHINA, ORDOVICIAN OF KENTUCKY M13 

Discussion.-The diagnostic features of Dalmanella 

multisecta are the combination of relatively small size 

and the stout subparallel brachiophore bases and wide 

sockets to accommodate the large teeth. This species is 

most similar to D. meeki, which has a slightly larger 

maximum size, more massive cardinalia, and, in some 

specimens, a more transverse outline and a more convex and more sulcate dorsal valve. Many specimens of 

the two species would be indistinguishable. 

Dalmanella fertilis is also similar to D. multisecta, 

but D. fertilis has generally less massive cardinalia 

with straight brachiophore bases and smaller sockets, 

and its dorsal valve is generally flatter and less 

sulcate. Some specimens of the two species would be indistinguishable, especially externally. 

Dalmanella multisecta is well separated stratigraphically from D. fertilis, which is older. D. meeki 

(Richmondian) apparently stratigraphically succeeds 

D. multisecta (Edenian-Maysvillian), according to Hall 

(1962). Better and more extensive collections than 

were. available for this study would probably show 

evolutionary gradation between the two species. My 

description of D. multisecta was based on 8 collections, 

only 3 of which had more than 12 specimens. 

Stratigraphic distribution.-Dalmanella multisecta 

was present in seven collections from the Kope Formation, ranging from the lower 20 ft to 212 ft above the 

base of the Kope (USGS collns. D-1314-CO, 

D-1315-CO, 7979-CO through 7981-CO). The species 

was also found in collection D-1363-CO, from the 

lower 37 ft of the Calloway Creek Limestone. The 

stratigraphic range for these collections is EdenianMaysvillian. 

Da1manella su1cata Cooper, 1956 

Plate 1, figures 25-38; plate 2, figures 1-14 

Dalmanella sulcata Cooper, 1956, p. 951-952, pl. 161, figs. 1-16; 

Neuman, 1967, p. 8-10, pl. 1, figs. 14-34. 

Diagnosis.-Medium size, length generally less 

than 16 mm; subcircular to subrectangular to slightly 

transversely elliptical in outline; ventral valve 

medium to highly convex for the genus (as much as 

6 mm); dorsal valve slightly convex (as much as 2 mm); 

distinct dorsal sulcus generally present, as much as 

1 mm deep; ventral valve subcarinate to gently rounded 

in posterior view. Seven to 9 costae and costellae, rarely 6 or 10, in 2-mm interval, measured 5 mm anterior 

to dorsal umbo; fila absent, prominent growth lines 

may be present. Ventral muscle field usually bilobed 

but may be cordate, extending to about midlength. 

Brachiophore processes convergent to median ridge 

and notothyrial platform; sockets generally bounded 

by posterolateral faces of brachiophore bases and 

floored by socket pads, fulcral plates present in some 

specimens; secondary deposits thicken brachiophore 

bases and cardinal process, especially shaft, in gerontic 

specimens. Very little secondary material on floor of 

valve, adductor muscle marks impressed in secondary 

material in some mature specimens; juvenile parts of 

posterior marks floor cavities beneath brachiophore 

bases, cavity may be filled by secondary deposits. 

Discussion.-An extensive description of D. sulcata 

was given by Neuman (1967). His analysis was based 

on most of the specimens that were used for my study. 

The most diagnostic features are the slightly convex sulcate dorsal valve and the distinctly convergent 

brachiophore bases and associated socket pads. Infraspecific variation occurs in (1) curvature of ventral 

valve, varying from subcarinate to gently rounded,· (2) 

outline of shell, and (3) alteration of dorsal interior 

because of the addition of secondary deposits, the most 

significant variation. In some collections (such as 

USGS 4051-CO and 5070-CO), secondary deposits 

thicken the cardinal process, brachiophore bases, and 

socket pads, and they- fill the cavity beneath the 

brachiophore bases. Also, dorsal muscle marks may be 

impressed in immature as well as in mature specimens. Such altered cardinalia resemble those of D. fertilis and even Heterorthina macfarlani, in which the 

main brachiophore bases are divergent to the valve 

floor. 

Stratigraphic distribution.-Dalmanella sulcata occurs principally in the Logana Member of the Lexington Limestone, and its presence is characteristic of that 

stratigraphic level. It is found in the lower part of the 

Grier Limestone Member of the Lexington (in USGS 

coHn. 5080-CO, Wilmore Quadrangle, and possibly in 

D-1197-CO, Frankfort East Quadrangle) at levels 

equivalent to the Logana elsewhere. The species was 

questionably identified in USGS collection 5023-CO 

from the top of the Curdsville Limestone Member of 

the Lexington in the Keene Quadrangle, in association 

with Dalmanella fertilis. Dalmanella sulcata is also 

present in collection 5085-CO, which came from a 

piece of float identified as Curdsville, at the Kentucky 

Utilities Plant Section in the Tyrone Quadrangle. 

The species is known from the lower part of the 

Hermitage Formation in central Tennessee (Cooper, 

1956) and from the Martinsburg Formation in Virginia 

(Walker, 1967, referred to as D. bassleri). Probably it 

occurs elsewhere but has been misidentified. 

Genus HETERORTHINA Bancroft 1928 

Type species.-H. praeculta Bancroft, by original 

designation. 

Discussion.-The most diagnostic feature of 

Heterorthina in the Kentucky area is the divergence of 

the brachiophore bases relative to their tops (described 

in the discussion of Dalmanella). Williams and Wright 

(1963) and Wright (in Williams and others, 1965) 
M14 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

described the genus as being similar to Onniella but 

stated that Heterorthina has a more convex pedicle 

valve, a subplanar brachial valve, and more splayed 

ventral diductor scars. Heterorthina macfarlani is the 

only species of the genus that I have seen. 

Heterorthina macfarlani Neuman, 1967 

Plate 3, figures 31-35; plate 4, figures 1-17 

Heterorthina macfarlani Neuman, 1967, p. 10-12, pl. 2, figs. 1-19. 

Diagnosis.-Large dalmanellid, as much as 21 mm 

long and 25 mm wide; transversely subelliptical in outline, cardinal extremities rounded except in some 

smaller specimens, anterolateral margins always 

rounded. Ventral valve moderately convex, as much as 

6 mm deep, subcarinate to gently rounded in posterior 

view, low fold present in some valves as much as 12 to 

15 mm long. Dorsal valve nearly flat but ranges from 

slightly convex through flat to resupinate; sulcus generally present in early growth stages, gradually 

shallowing and disappearing in specimens more than 

about 12 to 15 mm long; smaller specimens commonly 

have sulcate anterior margin. Seven to 9 costae and 

costellae, rarely 10, per 2-mm interval measured 5 mm 

anterior to dorsal umbo. Growth lines present or absent; where present, irregularly spaced and more 

prominent near margins of medium to large shells; fila 

absent. 

Ventral muscle field wide, with widely flaring dental plates enclosing pQsterior one-third of field; outline 

of field varying from almost cordate with adductor 

mark narrow, to more common bilobed shape with adductor track wide and one-half to three-fourths length 

of diductor marks; diductor marks extending from onethird to midlength of valve. 

Brachiophores with spikelike processes (rarely preserved) and with bases greatly divergent relative to 

their tops, so outer faces bound sockets, visible in plan 

view. Struts connect inner faces of brachiophore bases 

to median ridge and form notothyrial platform from 

which cardinal process rises; struts may be subparallel 

to valve floor or may slope inward toward midline of 

valve; platform elevated, cavity under struts on either 

side of median ridge, may be filled in larger specimens; 

short plates may be present under struts. Cardinal 

process shaft thin and myophore bulbous in very small 

specimens; myophore enlarged and distinctly bilobed 

in valves 8-10 mm long; shaft deeply cleft and greatly 

thickened during growth, occupying most of space between brachiophore supports, commonly wider than 

myophore in large valves. Median ridge broad, commonly with shallow median cleavage continuous with 

that of shaft of cardinal process. Adductor muscle 

marks preserved in some medium to large valves with 

secondary material thickening valve interior; marks 

extend from one-third to midlength of valve; anterior 

marks quadripartite to almost elliptical, posterior 

marks triangular and about equal in size to anterior 

marks. 

Discussion.-Neuman (1967) provided a description 

and a detailed discussion of the ontogeny of Heterorthina macfarlani, and our analyses agree closely. 

The cardinalia are the only features consistently 

reliable for differentiating Heterorthina macfarlani 

from species of Dalmanella. The large D. bassleri is 

most similar to Heterorthina macfarlani, but generally 

its ventral valve is less convex, more carinate, and has 

flatter posterolateral slopes. The ventral muscle field 

is not as wide, and the dorsal valve is slightly more 

convex, especially in smaller specimens. However, 

many specimens in both species are indistinguishable 

externally. As Neuman (1967) pointed out, H. macfarlani has been misidentified as Dalmanella (or Onniella) 

bassleri by others. Small to medium specimens of H. 

macfarlani can be similar externally to other smaller 

species of Dalmanella. Obviously, the two genera are 

closely related. 

Even the cardinalia of some specimens of H. macfarlani can resemble D. sulcata, depending on the 

development of the struts that form the notothyrial 

platform of Heterorthina. If the struts are inclined 

downward to the valve midline and are built far forward relative to the brachiophore bases, the struts look 

like the convergent brachiophore supports and the 

brachiophore bases, like the structure that forms the 

socket margin in D. sulcata. However, confusion of the 

two species is not likely except for collections of few, 

poorly preserved specimens. 

Stratigraphic distribution.-Heterorthina macfarlani occurs only within the Grier Limestone Member of 

the Lexington Limestone. It is apparently confined to 

the middle and upper part of the member, although it 

is rare or absent in the highest part of the Grier. 

Neuman (1967) stated that the species is confined to 

about one-fourth of the thickness of the Grier upward 

from about the middle of the member. 

LOCALITY REGISTER 

This locality register supplements those published 

by Pojeta (1979) and Parsley (1981) in Chapters A and 

K, respectively, of this series. The details of the numbering and the methods of notation are in Pojeta 

(1979). Only localities not mentioned in Chapters A 

and K are included here; therefore, refer to either 

Chapter A or K for any locality numbers used herein 

that are not listed in this register. 

Collection number---------4051-CO. 

Geographic location ------The same as for 5072-CO. 

Coordinates Do. 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA, AND HETERORTHINA, ORDOVICIAN OF KENTUCKY Ml5 

Formation ---------------Logana Member, Lexington Limestone. 

Stratigraphic position------48 ft above Tyrone Limestone-Lexington Limestone contact. 

Silicified ----------------Yes. ~ 

Quadrangle name ---------Frankfort East, Ky. 

Section name -------------Frankfort East B. 

Section number -----------87. 

Collection number---------4056-CO. 

Geographic location ------Quarry on east side of U.S. Route 27, 

3.1 mi south of Bryantsville, Ky., 

0.5 mi south of Burdette Knob. Stop 

14, Nosow and McFarlan (1960). 

Coordinates --------------384 mm east, 242 mm north. 

Formation ---------------Cornishville Bed(?), Perryville Limestone Member, Lexington Limestone. 

Silicified ----------------Yes. 

Quadrangle name ---------Bryantsville, Ky. 

Section name ------------Burdett Knob. 

Collection number---------4074-CO•. 

Geographic location -------The same as for 4072-CO. 

Coordinates Do. 

Formation ---------------Grier Limestone Member, Lexington 

Limestone. 

Stratigraphic position-----144 ft above the base of the Curdsville 

Limestone Member, Lexington Limestone. 

Quadrangle name ---------Tyrone, Ky. 

Section name-------------Tyrone A. 

Section number -----------89. 

Collection number---------4177-CO•. 

Geographic location -------Section at crossing of Kentucky Route 

169 and headwaters of Marble Creek. 

Coordinates--------------168 mm east, 573 mm north. 

Formation ---------------Curdsville Limestone Member, Lexington Limestone. 

Stratigraphic Position -----19.4 ft above Tyrone Limestone-Curdsville Limestone Member contact. 

Silicified ---------------Yes. 

Quadrangle name ---------Valley View, Ky. 

Section name -------------Marble Creek. 

Collection number---------4185-CO•. 

Geographiclocation -------The same as for 4178-CO. 

Coordinates Do. 

Formation ---------------Grier Limestone Member, Lexington 

Limestone. 

Stratigraphic position------136ft above the base of the section. 

Silicified ----------------Yes. 

Quadrangle name ---------Valley View, Ky. 

Section name-------------Valley View B (Hunters Ferry Rd.). 

Section number -----------34. 

Collection number---------4883-CO•. 

Geographic location -------The same as for 4871-CO. 

Coordinates Do. 

Formation ---------------Grier Limestone Member, Lexington 

Limestone. 

Stratigraphic position------60ft above the base of the section. 

Silicified ---------------Yes (75 lbs). 

Quadrangle name --------Valley View, Ky. 

Section name-------------Valley View C (Antioch Church Rd.). 

Section number-----------180. 

Collection number---------5070-CO•. 

Geographic location -------200ft north of 5069-CO. 

Coordinates Do. 

Formation ---------------Upper part of the Logana Member, 

Lexington Limestone. 

Quadrangle name ---------Frankfort East, Ky. 

Section name-------------Old Taylor. 

Collection number---------5085-CO. 

Geographic location -------The same as for 5081-CO. 

Coordinates Do. 

Formation ---------------Curdsville Limestone Member, Lexington Limestone. 

Stratigraphic position-----16 ft above Tyrone Limestone-Curdsville Limestone Member contact. 

Silicified ---------------Yes (2 lbs). 

Quadrangle name ---------Tyrone, Ky. 

Section name-------------Tyrone C (Kentucky Utilities Plant). 

Section number -----------17 4. 

Collection number---------5098-CO. 

Geographic location ------The same as for 4178-CO. 

Coordinates Do. 

Formation ---------------Grier Limestone Member, Lexington 

Limestone. 

Stratigraphic position------40-45 ft above base of section. 

Silicified ----------------Yes (15 lbs). 

Quadrangle name ---------Valley View, Ky. 

Section name-------------Valley View B (Hunters Ferry Rd.). 

Section number ----------34. 

Collection number--------6910-CO•. 

Geographic location ------The same as for 6909-CO. 

Coordinates Do. 

Formation ---------------Kope Formation. 

Stratigraphic position------66 ft above the Point Pleasant Tongue, 

Clays Ferry Formation-Kope Formation contact. 

Quadrangle name --------Falmouth, Ky. 

Section name -------------Falmouth A. 

Section number-----------195 

Collection number---------7833-CO. 

Geographic location -------Roadcut near intersection of Bull Fork 

Rd. and Righthand Fork Creek, west 

of Hamburg, Ind. 

Coordinates --------------322 mm east, 36 mm north. 

Formation --------------Lower part of the Saluda Formation. 

Silicified ----------------Yes (11 lbs). · 

Quadrangle name ---------Clarksburg, Ind. 

Section name -------------Hamburg. 

Collection number--------7979-CO. 

Geographic location ------The same as for 7978-CO. 

Coordinates Do. 

Formation ---------------Kope Formation. 

Stratigraphic position------Collected through lower 20 ft of Kope 

Formation. 

Quadrangle name ---------Demossville, Ky. 

Section name -------------Moffett Road. 
M16 CONTRIBUTIONS TO THE ORDOVICIAN PALEONTOLOGY OF KENTUCKY AND NEARBY STATES 

Collection number---------7980-CO. 

Geographic location -------The same as for 7978-CO. 

Coordinates Do. 

Formation ---------------Kope Formation. 

Stratigraphic position------130 ft above Point Pleasant Tongue, 

Clays Ferry Formation-Kope Formation contact. 

Quadrangle name ---------Demossville, Ky. 

Section name -------------Moffett Road. 

Collection number---------7981-CO. 

Geographic location -------The same as for 7978-CO. 

Coordinates Do. 

Formation ---------------Kope Formation. 

Stratigraphic position------212 ft above Point Pleasant Tongue, 

Clays Ferry Formation-Kope Formation contact. 

Quadrangle name ---------Demossville, Ky. 

Section name -------------Moffett Road. 

Collection number---------7983-CO. 

Geographic location -------The same as for 7823-CO. 

Coordinates Do. 

Formation ---------------Clays Ferry and Kope Formations, undivided. 

Stratigraphic position------Just above lowest occurrence of Sowerbyella rugosa. 

Quadrangle name ---------Monterey, Ky. 

Collection number---------D-1197 -CO•. 

Geographic location -------The same as for D-1196-CO. 

Coordinates Do. 

Formation --.-------------Grier Limestone Member, Lexington 

Limestone. 

Stratigraphic position------52 ft above the top of Tyrone 

Limestone. 

Quadrangle name ---------Frankfort East, Ky. 

Section name -------------Frankfort East A. 

Section number -----------86. 

Collection number---------D-1249-CO•. 

Geographic location -------The same as for D-1239-CO. 

Coordinates Do. 

Formation ---------------Bull Fork Formation. 

Stratigraphic position------43 ft above base of Bull Fork Formation. 

Quadrangle name ---------Orangeburg, Ky. 

Section name -------------County Line. 

Collection number---------D-1315-CO•. 

Geographic location -------The same as for D-1314-CO. 

Coordinates Do. 

Formation ---------------Fairview Formation. 

Stratigraphic position------51 ft above the base of the section. 

Quadrangle name ---------Maysville East, Ohio-Kentucky. 

Section name -------------Sleepy Hollow. 

Collection number---------D-1363-CO•. 

Geographic location -------The same as for D-1365-CO. 

Coordinates Do. 

Formation ---------------Calloway Creek Limestone. 

Stratigraphic position------Collected through the lower 37ft of the 

Calloway Creek Limestone. 

Quadrangle name ---------Richmond North, Ky. 

Section name-------------Type section of the Calloway Creek 

Limestone. 

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--- 1915, Bibliographic index of American Ordovician and 

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Foerste, A. F., 1909a, Preliminary notes on Cincinnatian fossils: 

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--- 1909b, Preliminary notes on Cincinnatian and Lexington fossils: Denison University Scientific Laboratories Bulletin, v. 14, p. 

289-334. 

--- 1910, Preliminary notes on Cincinnatian and Lexington fossils 

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---1914a, Notes on the Lorraine faunas of New York and the 

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Bulletin, v. 17, p. 247-340. 

--- 1914b, The Rogers Gap fauna of central Kentucky: Cincinnati 

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Hall, James, 1847, Descriptions of the organic remains of the lower 

division of the New York system: Paleontology of New York, v. 1, 

338 p. 

Hall, James, and Clarke, J. M., 1893, An introduction to the study of 

the genera of Paleozoic Brachiopoda: New York Geological 

Survey, Paleontology of New York, v. 8, pt. 1, 367 p. [1892]. 

Howe, H. J., 1966, Orthacea from the Montoya Group (Ordovician) 

of Trans-Pecos Texas: Journal of Paleontology, v. 40, no. 2, p. 

241-257. 

James, U. P., 1871, Catalogue of Lower Silurian fossils, Cincinnati 

Group: Cincinnati, Ohio, 14 p. 

Meek, F. B., 1873, Description of invertebrate fossils of the Silurian 

and Devonian systems: Ohio Geological Survey, v. 1, Geology and 

paleontology, pt. 2, Paleontology, p. 1-243. 
BRACHIOPOD GENERA HEBERTELLA, DALMANELLA. AND HETERORTHINA, ORDOVICIAN OF KENTUCKY 17 

Miller, S. A., 1875, Monograph of the class Brachiopoda of the Cincinnati Group: Cincinnati Quarterly Journal of Science, v. 2, p. 

6-62. 

Neuman, R. B., 1967, Some silicified Middle Ordovician brachiopods 

from Kentucky: U.S. Geological Survey Professional Paper 

583-A, p. A1-A14. 

Nosow, Edmund, and McFarlan, A. C., 1960, Geology of the central 

Bluegrass area [Guidebook]-Geological Society of America, 

Southeastern Section, Field Trip [No. 1]: Lexington, Ky., Kentucky Geological Survey, 54 p. 

Parsley, R. L., 1981, Echinoderms from Middle and Upper Ordovician 

rocks of Kentucky: U.S. Geological Survey Professional Paper 

1066-K, p. K1-K9. 

Peck, J. H., 1966, Upper Ordovician formations in the Maysville 

area, Kentucky: U.S. Geological Survey Bulletin 1244-B, p. 

B1-B30. 

Pojeta, John, Jr., 1979, The Ordovician paleontology of Kentucky 

and nearby States-Introduction: U.S. Geological Survey Professional Paper 1066-A, 48 p. 

Schuchert, Charles, and Cooper, G. A., 1932, Brachiopod genera of 

the suborders Orthoidea and Pentameroidea: Peabody Museum 

of Natural History Memoirs, v. 4, pt. 1, 270 p. 

Simmons, G. C., and Oliver, W. A., Jr., 1967, Otter Creek coral bed 

and its fauna, east-central Kentucky: U.S. Geological Survey 

Bulletin 1244-F, p. F1-F13. 

Walker, L. G., 1967, Stratigraphy of the Ordovician Martinsburg 

Formation in southwestern Virginia: Cambridge, Mass., Harvard University, Ph.D. dissertation, 147 p. 

Weir, G. W., and Greene, R. C., 1965, Clays Ferry Formation (Ordovician)-A new map unit in south-central Kentucky: U.S. 

Geological Survey Bulletin 1244-B, p. B1-B18. 

Weir, G. W., Greene, R. C., and Simmons, G. C., 1965, Calloway 

Creek Limestone and Ashlock and Drakes Formations (Upper 

Ordovician) in south-central Kentucky: U.S. Geological Survey 

Bulletin 1224-D, p. D1-D36. 

Whitfield, R. P., and Hovey, E. 0., 1898, Catalogue of the type and 

figured specimens in the paleontological collection of the 

geological department, American Museum of Natural History: 

American Museum of Natural History Bulletin 11, 500 p. 

Williams, Alwyn, and Wright, A. D., 1963, The classification of the 

"Orthis testudinaria Dalman" group of brachiopods: Journal of 

Paleontology, v. 37, no. 1, p. 1-32. 

Williams, Alwyn, and others, 1965, Brachiopoda, Pt. H of Moore, 

R. C., ed., Treatise on invertebrate paleontology: New York and 

Lawrence, Kans., Geological Society of America and University 

of Kansas Press, 2 v., 927 p. 
j 
PLATES 1-5 

Contact photographs of the plates in this report are available, at cost, from the U.S. Geological 

Survey Library, Federal Center, Denver, CO 80225. 
PLATE 1 

FIGURES 1-24. Dalmanella fertilis (Ulrich), 1909 (p. 11). 

1-4. Ventral valve; exterior, interior, posterior, and side views, x 2. USGS loc. 4177-CO, Curdsville Limestone Member, 

Lexington Limestone. USNM 258406. 

5. Ventral exterior, x 2. USGS loc. 4124-CO, Logana Member(?), Lexington Limestone. USNM 258407. 

6. Ventral exterior, x 2. USGS loc. 4124-CO, Logana Member(?), Lexington Limestone. USNM 258409. 

7. Interior of small ventral valve, x 4. USGS loc. 5069-CO, Curdsville Limestone Member, Lexington Limestone. 

USNM 258410. 

8. Ventral interior, x 2. USGS loc. 4124-CO, Logana Member(?), Lexington Limestone. USNM 258411. 

9. Ventral interior, x 2. USGS loc. 5022-CO, Curdsville Limestone Member, Lexington Limestone. USNM 258412. 

10. Dorsal exterior, x 2. USGS loc. 4124-CO, Logana Member(?), Lexington Limestone. USNM 258413. 

11, 12. Dorsal interior; cardinalia thickened by secondary deposits; ventral and anterior views, x 2. USGS loc. 4124-CO, 

Logana Member(?), Lexington Limestone. USNM 258414. 

13, 14. Dorsal interior; cardinalia thickened by secondary deposits; ventral and anterior views, x 2. USGS loc. 5022-CO, 

Curdsville Limestone Member, Lexington Limestone. USNM 258415. 

15, 16. Very small ventral valve; exterior and interior views, x 8. USGS loc. 5069-CO, Curdsville Limestone Member, 

Lexington Limestone. USNM 258416. 

17. Small dorsal valve with fulcral plate; anterolateral view, x 8. USGS loc. 5069-CO, Curdsville Limestone Member, 

Lexington Limestone. USNM 258417. 

18-21. Very small dorsal valve; exterior, interior, anterior, and anterolateral views, x 8. USGS loc. 5069-CO, Curdsville 

Limestone Member, Lexington Limestone. USNM 258418. 

22-24. Medium-sized dorsal valve; interior, anterior, and anterolateral views, x 4. USGS loc. 5069-CO, Curdsville Limestone Me~ber, Lexington Limestone. USNM 258419. 

FIGURES 25-38. Dalmanella sulcata Cooper, 1956 (p. 13). 

25-27. Very small dorsal valve; ventral, anterior, and anterolateral views, x 6. USGS loc. 5073-CO, Logana Member, 

Lexington Limestone. USNM 258420. 

28-30. Small dorsal valve; ventral, anterior, and anterolateral views, x 4. USGS loc. 5073-CO, Logana Member, Lexington 

Limestone. USNM 258421. 

31-33. Dorsal valve; ventral, anterior, and anterolateral views, x 2. USGS loc. 5073-CO, Logana Member, Lexington 

Limestone. USNM 258422. 

34-36. Large dorsal valve with thickened cardinalia. Ventral view, x 2; anterior and anterolateral views, x 4. USGS loc. 

D-1196-CO, Logana Member, Lexington Limestone. USNM 258423. 

· 37. ·Dorsal·exterior;·· x- 2. USGS··loc. fY-'!1196-CO;·-Logana·Member; Lexington-~Limestone:· USNM-258424. 

38. Cardinalia with fulcra! plates; anterolateral view, x 4. USGS loc. 5073-CO, Logana Member, Lexington Limestone. 

USNM 258425. 
DALMAN ELLA 
PLATE 2 

FIGURES 1-14. Dalmanella sulcata Cooper, 1956 (p. 13). 

1, 2. Small ventral valve; exterior and interior, x 4. USGS loc. 5073-CO, Logana Member, Lexington Limestone. USNM 

258426. 

3, 4. Ventral valve; exterior and interior, x 2. USGS loc. 5073-CO, Logana Member, Lexington Limestone. USNM 

258427. 

5. Ventral interior, x 2. Compare muscle marks with those in specimens shown in figures 2, 4, and 12. USGS loc. 

5092-CO, Logana Member, Lexington Limestone. USNM 258428. 

6-10. Articulated specimen; ventral, dorsal, side, posterior, and anterior views x 2. USGS loc. 5092-CO, Logana Member, 

Lexington Limestone. USNM 258429. 

11-14. Ventral valve; exterior, interior, side, and posterior views, x 2. Note relatively short hingeline. USGS loc. 4051-CO, 

Logana Member, Lexington Limestone. USNM 258430. 

FIGURES 15-28. Dalmanella bassleri Foerste, 1909 (p. 11). 

15, 16. Dorsal valve; exterior and interior, x 2. USGS loc. 7824-CO, Poin~· Ple~sant Tongue, Clays Ferry Formation. 

USNM 258431. 

17. Small ventral interior, x 2. USGS loc. 7824-CO, Point Pleasant Tongue, Clays Ferry Formation. USNM 258432. 

18-20. Fragment of dorsal valve showing cardinalia; ventral, anterior, and anterolateral views, x 4. USGS loc. 7824-CO, 

Point Pleasant Tongue, Clays Ferry Formation. USNM 258433. 

21. Fragment of dorsal valve showing cardinalia; anterior view, x 4. Compare angle between brachiophore bases with 

those in specimens shown in figures 19 and 23. USGS loc. 7824-CO, Point Pleasant Tongue, Clays Ferry Formation. USNM 258434. 

22-24. Smaller dorsal valve; ventral, anterior, and anterolateral views, x 4. USGS loc. 6146-CO, Point Pleasant Tongue, 

Clays Ferry Formation. USNM 258435. 

25-28. Ventral valve; exterior, posterior, side, and interior views, x 2. USGS loc. 7824-CO, Point Pleasant Tongue, Clays 

Ferry Formation. USNM 258436. 
DALMANELLA 
PLATE 3 

FIGURES 1-19. Dalmanella multisecta (Meek), 1873-(p.12). 

1. Ventral exterior, x 2. USGS loc. 7979-CO, lower part of the Kope Formation. USNM 258437. 

2, 3. Ventral valve; ventral and dorsal views, x 2. Compare curvature of valve with that shown in figure 5; USGS loc. 

7983-CO, Kope FormatiOOl. USNM 258438. 

4, 5. Ventral valve; ventral and dorsal views, x 2. USGS loc. 7981-CO, upper part of the Kope Formation. USNM 258439. 

6, 7. Ventral valve; exterior and interior views, x 2. USGS loc. uncertain. USNM 258440. 

8. Ventral interior, x 2. Compare muscle mark with that of specimen shown in figure 9. USGS loc. 7981-CO, upper 

part of the Kope Formation. USNM 258441. 

9. Ventral interior, x 2. USGS loc. 7983-CO, Kope Formation. USNM 258442. 

10. Dorsal exterior, x 2. Figures 17-19 show interior views of this valve. USGS loc. 7981-CO, upper part of the Kope 

Formation. USNM 258443. 

11, 12. Dorsal valve; exterior and interior views, x 2. USGS loc. 7981-CO, upper part of the Kope Formation. USNM 

258444. . 

13-16. Dorsal valve; ventral view, x 2; anterior, anterolateral, and posterior views, x 4. USGS loc. 7981-CO, upper part of 

the Kope Formation. USNM 258445. 

17-19. Dorsal valve; ventral, anterior, and anterolateral views, x 4. Thick secondary deposits. Figure 10 shows the exterior 

of this valve. USGS loc. 7981-CO, upper part of the Kope Formation. USNM 258443. 

FIGURES 20-30. Dalmanella meeki (Miller), 1875 (p. 12). 

20. Ventral exterior, x 2. USGS loc. D-1244-CO, Bull Fork Formation. USNM 258447. 

21. Small ventral interior; x 2. USGS loc. D-1255-CO, Bull Fork Formation. USNM 258448. 

22. Ventral interior, x 2. USGS loc. D-1249-CO, Bull Fork Formation. USNM 258449. 

23, 24. Dorsal valve; interior and exterior views, x 2. USGS loc. D-1244-CO, Bull Fork Formation. USNM 258450. 

25-27. Dorsal valve; ventral view, x 2; anterior and anterolateral views, x 4. USGS loc. D-1256-CO, Bull Fork Formation. 

USNM 258451. 

28-30. Dorsal valve; ventral view, x 2; anterior and anterolateral views, x 4. Very thick secondary deposits. USGS loc. 

D-1251-CO, Bull Fork Formation. USNM 258452. ' 

FIGURES 31-35. Heterorthina macfarlani Neuman, 1967 (p. 14). 

31-34. Ventral valve; exterior, interior, posterior, and side views, x 2. USGS loc. 5093-CO, Macedonia Bed, Grier Limestone Member, Lexington Limestone. USNM 258453. 

35. Ventral interior, x 2. USGS loc. 5093-CO, Macedonia Bed, Grier Limestone Member, Lexington Limestone. USNM 

258454. 
DALMANELLA AND HETERORTHINA 
PLATE 4 

FIGURES 1-17. Heterorthina macfarlani Neuman, 1967 (p. 14). 

1-3. Interior of a very small dorsal valve; ventral, anterior, and anterolateral views, x 12. USGS loc. 5093-CO, Macedonia Bed, Grier Limestone Member, Lexington Limestone. USNM 258455. 

4-6. Interior of a small dorsal valve; ventral view x 4; anterior and anterolateral views, x 8. USGS loc. 5093-CO, 

Macedonia Bed, Grier Limestone Member, Lexington Limestone. USNM 258456. 

7-9. Interior of a medium-sized dorsal valve; ventral, anterior, and anterolateral views, x 4. USGS loc. 5093-CO, 

Macedonia Bed, Grier Limestone Member, Lexington Limestone. USNM 258457. 

10. Interior of a large dorsal valve, x 2. USGS loc. 4852-CO, Grier Limestone Member, Lexington Limestone. USNM 

258458. 

11-13. Cardinalia of a large specimen; ventral, anterior, and anterolateral views, x 4. USGS loc. 5093-CO, Macedonia 

Bed, Grier Limestone Member, Lexington Limestone. USNM 258459. 

14. Dorsal exterior, x 2. USGS loc. 4852-CO, Grier Limestone Member, Lexington Limestone. USNM 258460. 

15. Ventral interior, x 2. USGS loc. 5093-CO, Macedonia Bed, Grier Limestone Member, Lexington Limestone. USNM 

258461. 

16-17. Ventral valve; exterior and interior views, x 2. USGS loc. 5093-CO, Macedonia Bed, Grier Limestone Member, 

Lexington Limestone. USNM 258462. 

FIGURES 18-40. Hebertella frankfortensis Foerste, 1909 (p. 3). 

18, 19. Exterior and interior of a very small ventral valve, x 4. USGS loc. 5016-CO, Cornish ville Bed, Perryville Limestone 

Member, Lexington Limestone. USNM 258463. 

20. Interior of a small ventral valve, x 4. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. USNM 

258464. 

21. Interior of a very small dorsal valve, x 4. USGS loc. 5016-CO, Cornishville Bed, Perryville Limestone Member, 

Lexington Limestone. USNM 258465. 

22, 23. Exterior and interior of a ventral valve. x 1. USGS loc. 4056-CO, Cornishville Bed(?), Perryville Limestone Member, Lexington Limestone. USNM 258466. 

24. Ventral interior, x 1. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. USNM 258467. 

25. Exterior of ventral valve with closely spaced costae, X 1. USGS loc. 4074-CO, Grier Limestone Member, Lexington 

Limestone. USNM 258468. 

26. Exterior of dorsal valve with closely spaced costae, x 1. USGS loc. 492~-CO, Grier Limestone Member, Lexington 

Limestone. USNM 258469. ' 

27. Dorsal valve with very low fold; anterior view, x 1. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. USNM 2584 70. 

28. Dorsal valve with fold; anterior view, x 1. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. 

USNM 258471. 

29-33. Articulated specimen; ventral exterior, dorsal exterior, posterior, anterior, and lateral views, x 1. USGS loc. 

5016-CO, Cornishville Bed, Perryville Limestone Member, Lexington Limestone. USNM 258472. 

34, 35. Exterior and interior of dorsal valve, x 1. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. 

USNM 2584 73. 

36. Ventral exterior, bifurcating costae, x 1. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. 

USNM 2584 7 4. 

37. Dorsal exterior, bifurcating costae, x 1. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. 

USNM 258475. 

38. Dorsal interior; anterior view, x 2. USGS loc. 4883-CO, Grier Limestone Member, Lexington Limestone. USNM 

258476. 

39, 40. Dorsal interior; ventral and anterior views, x 2. USGS loc. 4056-CO, Cornishville Bed(?), Perryville Limestone 

Member, Lexington Limestone. USNM 2584 77. 

. .......... ,._ , __ ..... .,. 
GEOLOGICAL SURVEY PROFES IONAL PAPER 1066-l\1 PLATE 4 
PLATE 5 

FIGURES 1-17. Hebertella parksensis Foerste, 1909 (p. 8). 

1, 2. Exterior and interior of a very small ventral valve, x 4. USGS loc. 7812-CO, Clays Ferry Formation. USNM 

258478. 

3-5. Small dorsal valve; exterior view, ventral and anterior views of the interior, x 4. USGS loc. 7349-CO, tongue of 

Clays Ferry Formation. USNM 2584 79. 

6. Dorsal interior; anterior view, x 1. USGS loc. 7353-CO, Millersburg Member, Lexington Limestone. USNM 

258480. 

7, 8. Exterior and interior of dorsal valve, x 1. USGS loc. 7353-CO, Millersburg Member, Lexington Limestone. USNM 

258481. 

9, 10. Exterior and interior of ventral valve, x 1. USGS loc. 7350-CO, Millersburg Member, Lexington Limestone. USNM 

258482. 

11. Interior of small ventral valve, x 1. USGS loc. 7348-CO, tongue of Clays Ferry Formation. USNM 258483. 

12. Articulated specimen with unusually convex valve flanks, anterior view, x 1. Collected by A. F. Foerste, Parks Hill, 

Nicholas County, Ky.; Millersburg Member, Lexington Limestone of current usage. Topotype specimen, USNM 

258446. 

13-15. Articulated specimen; ventral exterior, dorsal exterior, and lateral views, x 1. Parks Hill, Nicholas County, Ky.; 

Millersburg Member, Lexington Limestone of current usage. Syntype specimen, USNM 87054. 

16. Articulated specimen; anterior view, x 1. Collected by A. F. Foerste, Parks Hill, Nicholas County, Ky.; Millersburg 

Member, Lexington Limestone of current usage. Topotype specimen, USNM 84089. 

17. Dorsal interior; anterior view, x 2. USGS loc. 7353-CO, Millersburg Member, Lexington Limestone. USNM 

258484. 

FIGURES 18-41. Hebertella occidentalis (Hall), 1847 (p. 6). 

18, 19. Exterior and interior of very small ventral valve, x 6. USGS loc. 6409-CO, Calloway Creek Limestone. USNM 

258485. 

20, 21. Exterior and interior of very small dorsal valve, x 6. USGS loc. 6409-CO, Calloway Creek Limestone. USNM 

258486. 

22, 23. Exterior and interior of small ventral valve, x 2. USGS loc. 6409-CO, Calloway Creek Limestone. USNM 258487. 

24, 25. Exterior and interior of dorsal valve, x 2. USGS loc. 6409-CO, Calloway Creek Limestone. USNM 258488. 

26. Dorsal exterior, x 1. USGS loc. 6139-CO, upper part of the Dillsboro Formation. USNM 258489. 

27. Dorsal exterior; compare spacing of costae with specimen in fig. 26; x 1. USGS loc. 6139-CO, upper part of the Dillsboro Formation. USNM 258490. 

28. Dorsal exterior with sulcus, x 1. Same specimen as shown in fig. 32. USGS loc. 6139-CO, upper part of the Dillsboro 

Formation. USNM 258491. 

29. Ventral exterior, x 1. USGS loc. 6139-CO, upper part of the Dillsboro Formation, USNM 258492. 

30. Dorsal exterior, closely packed costae and costellae, x 1. USGS loc. 6139-CO, upper part of the Dillsboro Formation. 

USNM 258493. 

31. Dorsal exterior, x 1. USGS loc. 6139-CO, upper part of the Dillsboro Formation. USNM 258494. 

32. Dorsal exterior with sulcus; anterior view; same specimen as fig. 28; x 2. USGS loc. 6139-CO, upper part of the 

Dillsboro Formation. USNM 258491. 

33-37. Articulated specimen; ventral exterior, dorsal exterior, posterior, anterior, and lateral views, x 1. USGS loc. 

4556-CO, Back Bed, Tate Member, Ashlock Formation. USNM 258496. 

38. Ventral interior, x 1. USGS loc. 4556-CO, Back Bed, Tate Member, Ashlock Formation. USNM 258497. 

39-41. Dorsal interior; anterior, oblique anterior, and ventral views, x 1. USGS loc. 4556-CO, Back Bed, Tate Member, 

Ashlock Formation. USNM 258498. 
HEBERTELLA