An Early Keticuloceras 

Zone Fauna From the 

Hale Formation in 

Northwestern Arkansas

GEOLOGICAL SURVEY PROFESSIONAL PAPER 613-A

An Early Reticuloceras 

Zone Fauna From the 

Hale Formation in 

Northwestern Arkansas

By MACKENZIE GORDON, JR.

CONTRIBUTIONS TO PALEONTOLOGY

GEOLOGICAL SURVEY PROFESSIONAL PAPER 613-A

Descriptions and illustrations of nine 

Lower P ennsy Ivanian goniatites from the 

lower part of the Morrow Series

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1968
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEWART L. UDALL, Secretary

GEOLOGICAL SURVEY 

William T. Pecora, Director

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

Washington, D.C. 20402 - Price 45 cents (paper cover)
CONTENTS

	Page

Abstract _______________________________________________ Al

Introduction ___________________________________________ 1

Stratigraphic setting ____________________________ _ - 1

Collecting localities _____ ___.__________________________ 3

Cane Hill Member ______. _____________________________ 3

Prairie Grove Member ____.________________________ 3

Register of localities _________-_-_______ __ _ 4

UA (University of Arkansas) localities ______________ _ 4

USGS (U.S. Geological Survey) localities ________________________- 4

Other localities _____________-_______________-_ - 5

Reticuloceras tiro Assemblage Zone ________________ _ 5

Descriptions of species _________-_______ _ - "

References cited ____________- - __-__ ^"

Index ____________________________________ 21

ILLUSTRATIONS

[Plates follow index]

PLATE 1. Syngastrioeeras, Bisatoceras, Hudsonoceras, Reticuloceras?, and Cymoceras. 

2. Reticuloceras, Reticuloceras?, Branneroceras, and Stenopronorites.

Page

FIGURE 1. Index map showing collecting localities ________________________ -- _ A2

2. Syngastrioeeras globosum (Easton), cross sections and sutures ________ - _ 7

3. Bisatoceras paynei Gordon, external sutures of immature phragmocones __ _______ 8

4. Hudsonoceras moorei Quinn and Saunders, incomplete external sutures __-_____ 9

5. Cymoceras adonis n. sp., views of a paratype _________________ - 11

6. Cymoceras adonis n. sp., cross sections and sutures ______________ ______ 12

7. Reticuloceras tiro n. sp., cross sections and sutures ______________ 13

8. Reticuloceras? icaiiucrighti Quinn, cross sections and sutures ___________-_ 14

9. Reticuloceras? sp., external suture _________________________- - 16

10. Branneroceras semiretia (McCaleb), cross sections and suture _______ - 16

11. Branneroceras semiretia (McCaleb), suture of variant ___________ 17

12. Stenopronorites quinni n. sp., cross section and suture ____________ 17

in

CONTRIBUTIONS TO PALEONTOLOGY

AN EARLY RET1CULOCERAS ZONE FAUNA FROM THE 

HALE FORMATION IN NORTHWESTERN ARKANSAS

BY MACKENZIE GORDON, JR.

ABSTRACT

Nine species of goniatites occur in the upper part of the 

Cane Hill Member and the basal part of the Prairie Grove 

Member of the Hale Formation. These species comprise the 

earliest known cephalopod fauna from the Pennsylvanian 

rocks of North America. The Arkansas fossils occur in calcareous pebble conglomerate, calcareous sandstone, and sandy 

limestone. The stratigraphic interval in which all nine species occur and to which five of them appear to be restricted 

constitutes the Reticuloceras tiro Zone. This zone can be 

correlated approximately with the lowest subdivision of the 

Lower Reticuloceras (I^a) Zone of northwestern Europe including the British Isles.

The species described and figured in this paper are: Syngastrioceras globosum (Easton), Bisatoceras paynei Gordon, 

Hudsonoceras moorei Quinn and Saunders, Cymoceras adonis 

n. sp., Reticuloceras tiro n. sp., Reticulocerasl wainwrighti 

Quinn, Reticulocerasl sp., Branneroceras semiretia (McCaleb), 

and Stenopronorites quinni n. sp.

INTRODUCTION

The manuscript for the report on the Carboniferous cephaloids of Arkansas (Gordon, 1964) was 

completed before cephalopods were found in the 

Cane Hill Member of the Hale Formation. Most of 

the Cane Hill cephalopod localities were discovered 

by Professor J. H. Quinn, University of Kansas, 

and his students; through their indefatigable efforts 

a sizable collection, totaling some 600 specimens, 

was amassed. In 1961, Profesor Quinn kindly 

loaned these fossils to the author. Additional supplemental collections, totaling 145 specimens, from 

the University of Arkansas localities and from one 

new locality, were made by the writer in company 

with Professor Quinn and his students or with 

members of the U.S. Geological Survey. All these 

collections constitute the basis for the fossil descriptions given here.

STRATIGRAPHIC SETTING

The fauna described in this paper occurs in 

roughly the ui:per half of the Cane Hill Member of 

the Hale Formation and locally in the basal 1-3 

feet of the Prairie Grove Member. Most of the anmonoids were found in 1- or 2-foot thick claystonepebble conglomerate beds, which are associated 

with calcareous sandstone beds that occur as lenses 

in the typical shale of the Cane Hill Member. Shells 

of some of the small species, particularly those of 

Reticuloceras, were generally found incorporated 

within claystone pebbles; many of the larger 

shells which occur in the conglomerate matrix, are 

fragmental. These were death assemblages (thanatocoenoses), but reworking of the fossils is not 

believed to have mixed species of very different 

ages, as these ammonoids were approximately contemporaneous inhabitants of the early Morrow Sea.

No ammonoids have been found in the shale, 

which is silty to finely arenaceous and singularly 

devoid of fossils. The shale is commonly riprje 

marked and contains many thin lenticules of finegrained sandstone that locally weather out as 

wafers an inch or two in diameter.

At the locality near Cane Hill (fig. 1, loc. 1), this 

fauna occurs in a 6-foot thick unit consisting of 

sandy limestone and calcareous sandstone. The fcssiliferous unit is separated from the underlying 

Pitkin Limestone by a 6-foot bed of siltstone containing a basal few inches of shale and lenticular 

bodies of pebble conglomerate. This lithology resembles that of the Prairie Grove Member of the 

Hale Formation, but L. G. Henbest (oral commun., 

1961) traced the sandstone unit laterally and discovered that it fingers into the typical platy shale lithology of the Cane Hill Member.

Al
A2 CONTRIBUTIONS TO PALEONTOLOGY

94°20'

|j||f-Area of figure 1

WASHINGTON COUNTY

94°30

94°00'

FIGURE 1. Collecting localities for Lower Pennsylvanian ammonoids. University of Arkansas and U.S. Geological Survey 

locality numbers for these sites are given in the register of localities (p. A4).
AN EARLY RETICULOCERAS ZONE FAUNA A3

The combined lithologic and faunal evidence indicates that the sediments of the Hale Formation 

were laid down in relatively shallow water, probably in the shallow part of the neritic zone.

COLLECTING LOCALITIES

The ammonoids described herein come from 

seven localities in the lower and middle parts of 

the Hale Formation. The localities, all in Washington County, Ark., are shown on the index map 

(fig. 1). Five of these are in the Cane Hill Member, 

and two are probably in the Prairie Grove Member.

CANE HILL MEMBER

At two of the five Cane Hill localities the ammonoids occur in pebble-conglomerate beds associated 

with calcareous sandstone lenses within typical 

shale and siltstone of the Cane Hill Member. These 

two localities are at the Fayetteville Country Club 

and at Sequoyah (East) Mountain. At the Fayetteville Country Club (fig. 1, loc. 3), the following 

species have been found.

Number collected

Syngastrioceras globosutn (Easton) _______ 205

Bisatoceras paynei Gordon ____________ 1

Hudsonoceras moorei Quinn and Saunders __ 2

Reticuloceras tiro n. sp _______________ 11

Reticuloceras? wainwrighti ____________ 10

Branneroceras semiretia (McCaleb) _______ 29

Cymoceras adonis n. sp ______________ 18

Stenopronorites guinni n. sp ___________ 4

Also, on the east slope of Sequoyah (East) Mountain (fig. 1, loc. 5) the following were collected:

Number collected

Syngastrioceras globosum (Easton) ______ 16

Reticuloceras tiro n. sp ______________ 4

Branneroceras semiretia (McCaleb) _______ 3

Cymoceras adonis n. sp _______________ 3

At a locality (fig. 1, loc. 2) northwest of Greenland, the fossils occurred in a large block of conglomeratic sandstone lying loose in the middle of 

a moderately thick but largely covered section of 

shale of the Cane Hill Member. How far the block 

had moved is not known. This locality has been 

discussed and figured by Quinn (1966, p. 13, 18, 

text fig. 2), who believed the block was approximately in place when found. The locality has been 

obliterated by the construction of a road. Material 

from this locality is as follows:

Number collected

Syngastrioceras globosum (Easton) _______ 49

Bisatoceras paynei Gordon ____________ 2

Hudsonoceras moorei Quinn and Saunders _ 1

Reticuloceras tiro n. sp _______________ 18

Reticuloceras? wainwrighti Quinn _ 

Reticuloceras? sp _____________

Branneroceras semiretia (McCaleb) 

Cymoceras adonis n. sp _________

Stenopronorites quinni n. sp ______

Number collected

.__ 6

___ 1

.__ 2

.__ 7

.__ 3

Locality 4 of figure 1 is in the east wall of a 

railroad cut in the town of Fayetteville. The fossils 

come from a limestone bed in the lower part of 

the formation at this locality. However, as the 

Cane Hill Member is transgressive and unconformably overlies the Fayetteville Shale at this place, 

it is possible that the lowest beds of the Cane Hill 

are absent here. The small collection consists of 

the following species:

Syngastrioceras globosum (Easton) . 

Reticuloceras tiro n. sp ______- 

Branneroceras semiretia (McCaleb) 

Cymoceras adonis n. sp _______.

Number collected 

____ 1 

___ 1

__ 3 

5

Locality 1 of figure 1, in a quarry near Cane Hill, 

has been discussed above. This locality also was 

described and shown in a photograph and diagrammatic sketch by Quinn (1963, p. 26-28, figs. 1, 2), 

who regarded the ammonoid-bearing bed as belonging in the Cane Hill Member. The ammonoid 

fauna collected here is as follows:

Number collected

Syngastrioceras globosum (Easton) _______ 50

Bisatoceras paynei Gordon _____________ 5

Hudsonoceras moorei Quinn and Saunders __ 1

Reticuloceras tiro n. sp ______________ 7

Reticuloceras? wainwrighti Quinn _______ 5

Branneroceras semiretia (McCaleb) _______ 80

Cymoceras adonis n. sp ______________ 16

Stenopronorites quinni n. sp ___________ 6

PRAIRIE GROVE MEMBER

Collections from two localities come from beds 

believed to belong in the lower part of the Prairie 

Grove Member. At one of these localities, near St. 

Joseph Cemetery, about 3V2 miles northeast of Fayetteville (fig. 1, loc. 6), the fossils are from a thin 

bed of weathered calcareous sandstone a few feet 

above typical dark-gray siltstone of the Cane Hill 

type. This bed contains the fauna typical of the 

upper part of the Cane Hill Member:

Number collected

Syngastrioceras globosum (Easton) _______ 81

Reticuloceras tiro n. sp ______________ 18

Reticuloceras? wainwrighti Quinn _______ 7

Branneroceras semiretia (McCaleb) _______ 12

Cymoceras adonis n. sp ______________ 8

At the other locality (fig. 1, loc. 7), the fossils 

are in a partly coquinoid limestone grading intc
A4 CONTRIBUTIONS TO PALEONTOLOGY

light-gray sandy limestone. It is possible, judging 

partly from the lithology, that this assemblage 

represents a slightly higher zone. The species positively identified are those that range higher into 

the Prairie Grove Member. The ammonoids collected are as follows:

Number collected

Syngastrioceras globosum (Easton) ______ 13

Bisatoceras paynei Gordon ____________ 1

Reticuloceras? wainwrighti Quinn ______ 1

Branneroceras semiretia (McCaleb) ______ 9

Cymoceras adonis n. sp ______________ 1

REGISTER OF LOCALITIES

UA (UNIVERSITY OF ARKANSAS) LOCALITIES

L14 (fig. 1, loc. 4). Fayetteville TVij-minute 

quadrangle. St. Louis and San Francisco Railway 

cut, east side, 10 feet north of the Maple Street 

overpass, near center of south line of sec. 9, T. 

16 N., R. 30 W., in town of Fayetteville, Ark. Limestone lens in Cane Hill Member of Hale Formation, 

approximately 15 feet stratigraphically above contact of Fayetteville Shale and Hale Formation. 

Collector, J. H. Quinn.

L18 (fig. 1, loc. 2). Fayetteville TV^-minute 

quadrangle. On east side of dirt road along southwest-trending ridge that lies about midway between Round Top Mountain and south summit of 

Kessler Mountain, in NE^NW^NW^ sec, 6, T. 

15 N., R. 30 W., about 700 feet south of bend in 

road at township line and 1% miles west-northwest 

of Greenland, Ark. Sandy limestone block in Cane 

Hill Member of Hale Formation, 28 feet above 

top of Pitkin Limestone. Collector, L. L. Wainwright.

L59 (fig. 1, loc. 7). Sonora 7 1/2 niinute quadrangle. On east bank of southeast-flowing intermittent stream, 60 feet north of east-west road, in 

SWi/iSEiANWi/4 sec. 21, T. 17 N., R. 29 W., about 

three-fourths of a mile east of Zion School, Washington County, Ark. Fossils from light-gray sandy 

limestone, presumably Prairie Grove Member of 

Hale Formation that rests on ripple-marked siltstone of Cane Hill Member and is beneath lower 

fossiliferous limestone of Brentwood Limestone 

Member of Bloyd Formation. Collector, David Metz.

L61 (fig. 1, loc. 3). Fayetteville 7i/2 -minute 

quadrangle. Outcrop on east slope of South Mountain, about 950 feet south-southeast of Fayetteville 

Country Club clubhouse and 125 feet east of dirt 

road, at approximately 1,500 feet elevation, in NE 

*/4 NEi/4 NW!/4 sec. 34, T. 16 N., R. 30 W. Calcareous and conglomeratic sandstone lenr in Cane 

Hill Member of Hale Formation; fossiliferous bed 

15 feet above top of Pitkin Limestone.

L62 (fig. 1, loc. 6). Elkins 7i/2minute quadrangle. Outcrop in intermittent stream gully just 

beyond fence at east side of south-trending road, 

one-fourth of a mile east of St. Joseph Cemetery 

and one-fourth of a mile south of Arkansas Highway 45, approximately on township line at west 

side of SW1/4SW1/4NW1/4 sec. 6, T. 16 N., R. 29 W., 

31/2 miles northeast of Fayetteville, Ark. Fossils 

from 2- to 4-inch layer of sandy limestone at base 

of massive calcareous sandstone, presumably Prairie Grove Member of Hale Formation, a little above 

flaggy ripple-marked siltstone beds of Cane Hill 

Member. Collector, David Metz.

L77 (fig. 1, loc. 1). Winslow 30-minute quadrangle. Beds in upper part of east face cf quarry, 

half a mile north of Cane Hill and a little east 

of Arkansas Highway 45, in SW14SW14 sec. 4, 

T. 14 N., R. 32 W., Washington County, Ark. (Pitkin loc. 16 of Easton, 1943, p. 153.) Fossils from 

limestone conglomerate about 10 feet above PitkinHale contact. Collectors, J. H. Quinn, George 

Staley, and B. F. Clardy.

USGS (U.S. GEOLOGICAL SURVEY) LOCALITIES

19700-PC (fig. 1, loc. 6). Same locality and 

horizon as UA loc. L62. Collectors M. Gordon, 

J. H. Quinn, H. E. Garner, George Staley, William 

Dial, and William Bishop, November 29, 19SO.

19701-PC (fig. 1, loc. 7). Same locality and 

horizon as UA loc. L59. Collectors, M. Gordon, J. H. 

Quinn, and others, November 29, 1960.

19702-PC (fig. 1, loc. 3). Same locality and 

horizon as UA loc. L61. Collectors, M. Gordon, 

J. H. Quinn, and others, November 29,1960.

19981-PC (fig. 1, loc. 1). Same locality and 

horizon as UA loc. L77. Collectors, M. Gordon, J. H. 

Quinn, and John Hutchison, April 1961.

22012-PC (fig. 1, loc. 5). Fayetteville 7V2 - 

minute quadrangle. Outcrop at foot of elm tree on 

west bank of southeast-trending intermittent drainage on east slope of Mount Sequoyah, approximately in the more western of two power]ine lanes, 

100 feet downstream from 8-foot waterfall marking base of Prairie Grove Member, NWViNE1/^,- 

NW1/4NW1/4 sec. 14, T. 16 N., R. 30 W., Washington County, Ark. Fossils from 1-foot thick claystone conglomerate below 4 feet of fine-grained 

slabby sandstone; top of fossiliferous bed is 8 feet 

stratigraphically below top of Cane Hill Member of
AN EARLY RETICULOCERAS ZONE FAUNA

Hale Formation. Collectors, H. D. Miser, M. Gordon, and L. G. Henbest, October 20-21, 1961.

OTHER LOCALITIES

Three other ammonoid localities in the Cane Hill 

Member of the Hale Formation have been mentioned in the literature, but were not covered in 

the present study. One locality, which was the source 

of the holotype and paratype of Branneroceras semiretia (McCaleb), is on the east side of a railroad 

cut of the St. Louis and San Francisco Railway Co. 

in Fayetteville, Ark., one block east of the campus of 

the University of Arkansas. It lies about 100 yards 

south of UA locality L14.

The second locality (UA loc. L117) provided 

most of the type specimens of Hudsonocems moorfi 

Quinn and Saunders and lies half a block south 

of UA locality L14 on the same side of the same 

railroad cut.

The third locality (UA loc. L99) yielded the holotype of Reticulocerasl wainwrighti Quinn. The outcrop is in the bed of a small intermittent stream, 

100 yards south of the West Fork-Moffet road, 

about 21/2 miles southwest of its junction with 

U.S. Highway 71 at West Fork, and it is in the 

SE. cor. sec. 1, T. 14 N., R. 31 W., Washington 

County, Ark. The fossils occur in a calcareous pebble-conglomerate bed associated with flaggy siltstone and some sandstone. The fossil-bearing bed 

is overlain by brown-weathering- sandstone of the 

Prairie Grove Member of the Hale Formation, 

and for mapping purposes, probably should be included with that member. However, the lithologic 

similarity to ammonoid-bearing conglomerates at 

the Fayetteville Country Club and Sequoyah 

Mountain localities indicates that Quinn (1966, p. 

18) was probably correct in considering the conglomerate at this locality as part of the Cane Hill 

Member.

RETICULOCERAS TIRO ASSEMBLAGE ZONE

The ammonoid assemblage collected in the upper part of the Cane Hill Member and locally in the 

basal part of the Prairie Grove Member of the 

Hale Formation so far totals nine species, as follows:

Syngastrioceras globosum (Easton) 

Bisatoceras paynei Gordon 

Cymoceras adonis n. sp.

*Hudsonoceras moorei Quinn and Saunders

*Reticuloceras tiro n. sp.

*Reticuloceras? wainwrighti Quinn

*Reticuloceras? sp.

*Branneroceras semiretia (McCaleb) 

Stenopronorites quinni n. sp.

These species constitute the Reticuloceras tiro assemblage, and that part of the Morrow Series 

rocks that they occupy can be considered the 

Reticuloceras tiro Assemblage Zone. This zone is 

stratigraphically the lowest known Pennsylvanian 

ammonoid zone in the United States. Species 

marked with an asterisk (*) in the list above are 

restricted to this zone. The others range higher.

As nearly as can be determined, the Reticuloceias tiro Zone is approximately equivalent to tr.e 

R. compressum (Rja) Subzone of the lower 

Reticuloceras (Ri) Zone in the northwest European Carboniferous section. In Europe and the 

British Isles the Lower Reticuloceras Zone immediately succeeds the Homoceras (H) Zone; however, neither the genus Homoceras nor the Homoceras Zone have been positively recognized in 

the United States. It is possible that in Arkansas 

the lower part of the Cane Hill Member of the Hale 

Formation, which so far has yielded no ammonoids, 

is the temporal equivalent of the Homoceras Zone, 

but it also is possible that the Homoceras Zone 

is Late Mississippian in age.

The Reticucloceras tiro Zone is followed strat'- 

graphically by an ammonoid zone in which the 

most abundant species generally is either Reticuloceras henbesti (Gordon) or Arkanites relictus 

(Quinn, McCaleb, and Webb). This assemblage occurs through the greater part of the Prairie Grove 

Member of the Hale Formation.

DESCRIPTIONS OF SPECIES 

Genus SYNGASTRIOCERAS Librovitch, 1938

Syngastrioceras Librovitch, 1938, p. 81, 82, 103, 104; Ruzhercev and others, 1962, p. 376. 

Eoasianites, Miller, Furnish, and Schindewolf [part], 1957,

p. L61.

Glaphyrites, Gordon [part], 1965 [1964 imprint], p. 218-221. 

Diagnosis. Glaphyrites-like conch, globose to 

subglobose in immature and early mature stages 

becoming thickly discoidal in adult in some specie?, 

involute to moderately evolute; umbilicus stepped 

within. Surface smooth, with angular to subangrlar umbilical shoulder, thickened into spiral core1 ; 

spatulate saddles; first lateral lobe protruding 

slightly further apicad than prongs of ventral lobe.

Type species. Gastrioceras orientate Yin, 1935, 

by original designation.

325-387 O - 68 - 2
A6 CONTRIBUTIONS TO PALEONTOLOGY

Discussion. The ammonoid group considered 

under this name is in number of individuals by 

far the most abundant in the Reticuloceras tiro 

Zone. Although it has been customary in the United 

States to assign these shells to Eoasianites, or to 

Glaphyrites which some paleontologists regard as 

congeneric with Eoasianites, there is some justification for regarding them as a distinct group. 

They can be recognized by the shape of the suture 

line and by their ornamentation in the vicinity 

of the umbilicus. Moreover, shells of this type seem 

to be confined to Lower Pennsylvania!! rocks.

In discussing several natural subdivisions of the 

shells that he was including in Glapkyrites, Gordon (1964, p. 220) singled out in the first group 

those forms that "have a stepped umbilicus commonly ornamented with a single cord of flat keel 

along the shoulder, as in G. morroivensis (Miller 

and Moore) and G. oblatus Miller and Moore." 

This group is synonymous with Syngastrioceras. 

Although Yin (1935, p. 20) did not mention a cord 

or keel along the "apparently angular" umbilical 

shoulder in Gastrioceras orientate Yin, he did mention a "spiral thickening" along the angular umbilical shoulder of the associated and closely related form G. suborientale Yin (1935, p. 20). Yin's 

wording suggests that wear had partly obscured 

the ornament of the umbilical shoulder in G. orientate, and his illustrations of primary types of 

that species bear this out.

Ruzhentsev and others (1962, p. 376) said that 

the growth striae in Syngastrioceras generally 

project forward and are indented by an incipient 

sinus. This is a character that also occurs in typical Glaphyrites and does not necessarily distinguish Syngastrioceras from other genera similar 

in form. The principle distinguishing feature of 

Syngastrioceras is its umbilical shoulder which has 

a single keel or cord, in contrast to the fine transverse riblets ornamenting the umbilical shoulder 

of both Glaphyrites and Eoasianites.

Included in the genus Syngastrioceras are Glaphyrites depressus Gordon, Cravenocerast morrowense Miller and Moore [part], Goniatites nolinensis Cox, Glaphyrites oblatus Miller and Moore, 

Gastrioceras orientale Yin, G. suborientalis Yin, 

and Syngastrioceras uralicus Librovitch. These 

gpecies are restricted to the Lower Pennsylvanian 

Morrow Series in the United States and the Bashkirian Stage and equivalent rocks in Europe and 

Asia.

Syngastrioceras is probably ancestral to the late 

Morrow and Atoka subgenus Pseudoparalegoceras

(Phaneroceras), which developed into Pseudoparalegoceras s. s. in the Des Moines Series. Phaneroceras has a conch with a keeled shoulder, rather 

similar to that of Syngastrioceras. Its suture differs from that of Syngastrioceras in that the 

prongs of the ventral lobe are somewhat larger 

and deeply divided by the median saddle. The 

prongs approach though do not attain the size of 

the first lateral lobe. Typical Syngastrioceras apparently do not occur in rocks younger than Morrow in age.

Syngastrioceras globosum (Eastern)

Plate 1, figures 1-7; text figure 2A-G 

Eoasianites globosus Easton, 1943, p. 152, pi. 24, fig. 16;

Clardy, 1962, p. 105, 106, pi. 1, figs. 1, 2, pi. 2, fig. 5. 

Eoasianites oblatus (Miller and Moore), Clardy, 19i"2, p. 106,

pi. 1, fig. 3. 

Glaphyrites globosum (Easton), Gordon, 1965 [1964 imprint],

p. 222, 223, pi. 23, figs. 16-18, text fig. 61A, B.

The holotype of this species has been rec1 escribed 

by Gordon (1964, p. 222), and its characters are 

fairly well established. The present study, however, based on more than 400 specimens from the 

lower middle part of the Hale Formation, 1 as demonstrated a surprising range of variation in the 

species. Two forms can be recognized and are present at all localities. The typical form, represented 

by the holotype and similar evolute shell*51 , has a 

barrel-shaped conch with diameters of as much as

1 inch (25 mm) or slightly more; the umbilicus 

ranges from about one-third to nearly one-half the 

diameter of the conch. In this form, the width of 

umbilicus/diameter ratio lessens proportionally 

with growth and the width/height of whorl ratio 

lessens markedly once the cadicone (barrel-shaped) 

stage is passed and the whorl takes on greater 

height and curvature in cross section. A typical 

specimen is shown in cross section in tert figure

2 A, B.

The other form, much less common than the 

typical one, is involute; the width of the umbilicus 

ranges from about one-fifth to a little more than 

a fourth the diameter of the shell. One of these 

shells is shown in cross section in text figure 2, 

C, G. The suture of Syngastrioceras globosum has 

strongly hastate lobes (text fig. 2 B, D, E). The 

relatively narrow width of the first lateral lobe is 

the principal distinguishing feature that separates 

it from S. oblatum (Miller and Moore) of the 

Bloyd Shale. In some specimens of the involute 

form of S. globosum, the first lateral lobe is 

slightly wider than in the typical form, but this is 

to be expected because the shell surface traversed
AN EARLY RETICULOCERAS ZONE FAUNA

FIGURE 2. Syngastrioceras globosum (Easton). A, F, Cross sections of typical form (USNM 147664), x 1%, X 5. B, Suture 

of typical form (USNM 146381), x 2%, where H=8.3 and W=22 mm. C, G, Cross section of involute form (USNM 

146383), x 1%, X 5. Q, External suture of involute form (USNM 146382), x 2, where D=22, H = 11.2, and W=18.2 

mm. E, External suture of typical form (USNM) 146379), x 2, where D = 33, H = 12.3, and W=22 mm. Topotypes include A and F from USGS loc. 19981-PC and E from UA loc. L77; B-D and G are from UA loc. L61.

by the suture is greater in the involute form. In 

other specimens, however, the first lateral lobe is 

about the same width in both forms. The two forms 

have a tendency to intergrade, but there does not 

seem to be a complete intergradation.

The involute form is considerably scarcer at ?.ll 

localities than the typical evolute one, the overp.il 

ratio being 1:6.1 or roughly 16 percent. At the 

locality where the involute form was relatively the 

most common (UA loc. L61, USGS loc. 19702-PC),

Typical form1 Involute form2

Dimensions (mm):

Diameter (D) ______.

Height of last whorl (H)

Width of last whorl (W)

Width of umbilicus (U) _. 

Proportions:

U/D ____________.

W/D ____________.

W/H

USNM

146381

55.5

24.7

39.4

16.5

.30

.71

1.60

USNM

146380

33.5

13.0

28.0

14.5

.43

.83

2.18

UC 4819-2

Holotype

18

5.5

17

8.5

.47

.94

3.09

USNM

146382

24.2

12.8

18.7

6.5

.27

.77

1.46

USNM

146383

23.4

11.5

18.2

6.5

.28

.77

1.58

USNM

146384

21.0

10.8

16.6

4.5

.21

.79

1.53

1 Typical forms are from the type locality, UA loc. L77. 

a Involute forms are from UA loc. L61. The holotype, designated by UC48192 (Univ. of Chicago specimen no.), formerly in the Walker Museum 

is now in the Chicago Museum of Natural History.
A8 CONTRIBUTIONS TO PALEONTOLOGY

172 specimens of the typical form and 33 of the 

involute form were found, a ratio of 1:5.2 or 19 

percent. At the locality where the involute form 

was relatively least common (UA loc. L62, USGS 

loc. 19700-PC), 76 of the typical form and five of 

the involute form were collected, a ratio of 1:15.2 

or not quite 7 percent.

An analogous range of variation is found in the 

species of Syngastrioceras that is abundant in the 

Brentwood Limestone Member of the Bloyd Shale. 

The less involute form was described as Glaphyritep 

oblatus Miller and Moore (1938, p. 352 and Gordon, 1964, p. 224). A specimen of the more involute form was included in the syntypes of 

Cra/ve?wcerasl morrowense Miller and Moore 

(1938, p. 346, pi. 43, fig. 1, text fig. 2B), and this 

form was identified as Glaphyrites morrowensis 

(Miller and Moore) by Gordon (1964, p. 223). It 

seems, however, that the syntypes of Cravenocerast morrowense included more than one species 

and genus. A designation of a lectotype for this 

species is included in a manuscript on the ammonoid fauna of the Bloyd Formation of Arkansas 

by J. A. McCaleb (unpub. data). The earliest 

name for the Bloyd species seems to be Goniatites 

nolinensis Cox (1857), but the writer has hesitated to use this name until a primary type or at 

least a topotype of the Kentucky species can be 

found.

Tijpes. Holotype UC 48192; hypotypes USNM 

146379-146384, 147664.

Occurrence. Hale Formation, Cane Hill Member, 

UA Iocs. L14, L18, L61, L77, USGS Iocs. 19702- 

PC, 19981-PC, 22012-PC; probable Prairie Grove 

Member UA Iocs. L59, L62, USGS Iocs. 19700-PC, 

19701-PC; Washington County, Ark. The holotype 

is from Easton loc. 16=UA loc. L77=USGS loc. 

19981-PC, Cane Hill, Ark.

Genus BISATOCERAS Miller and Owen, 1937 

Bisatoceras paynei Gordon

Plate 1, figures 8-11; text figure 3A, B

Bisatoceras paynei Gordon, 1965 [1964 imprint], p. 249, 250, 

pi. 28, figs. 40-47, text figs. 74A, B.

Seven specimens from three localities are referred to this species. The specimens show the 

well-rounded venter merging with very gently 

rounded flanks. In specimens less than 7 mm in 

diameter, the flanks slope inward and the umbilicus lies in the center of a broad shallow depression. This depression remains during growth but 

stays about the same size, so that in adult specimens it is limited to the immediate area of the

FIGURE 3. Bisatoceras paynei Gordon, external sutures of immature 

phragmocones. A, Hypotype (USNM 

146386),X5, where H = 6.5 and W= 

9.0 mm. B, Hypotype (USNM 146- 

387), X 14, where H=3.5 and W= 

5.5 mm. A is from UA loc. L18 and 

B is from UA loc. L77.

umbilicus. The greatest width of the shell occurs 

just outside of the depressed area. Adult shells are 

thick discoidal, but early stages are globose, to subglobose. One small specimen seems to have a tiny 

open umbilicus. (See table of measurements below.) 

Fine sinuous growth striae separate broader 

lamellae, which resemble the lamellae in Cravenoceras. These growth striae form a very shallow orad 

bow over the venter, a deeper sinus over each ventrolateral zone, and a shallow orad bow on each 

flank, as in the holotype. Rarely, on internal molds 

of immature phragmocones, the growth lamellae 

are expressed as transverse undulations on the venter and ventrolateral zones. Growth constructions 

occur sporadically in this species, generally not 

more than one, or very rarely two, per whorl.

At a shell diameter of 6 mm (text fig. 35), the 

suture has a rather short, broad ventral lobe; its 

sides curving outward and its prongs rarrowly 

rounded at the tip; the first lateral saddle is 

broadly arched and slightly asymmetrical. The 

first lateral lobe is also broad and short and ends 

in a blunt point. At a diameter of 12 mm (text 

fig. 3A), the sides of the prongs of the ventral 

lobe of the suture are fairly straight and parallel; 

the lobes are a little longer and narrower than 

in the earlier stages, and the first lateral lobe is 

mamillate. The suture of a specimen at a shell 

diameter of 18 mm has already been illustrated 

and described by Gordon (1964, p. 250, text fig. 

745).

This species ranges through most of the Hale 

Formation. The holotype came from near the top 

of the Prairie Grove Member and the paratype 

from 2 to 3 feet above its base (Gordon, 1964, 

p. 40-42). The present hypotypes are from the
AN EARLY RETICULOCERAS ZONE FAUNA A9

middle and upper parts of the Cane Hill Member. 

These provide new information as to the shape, 

dimensions, and configuration of the sutures in 

less mature specimens.

1USNM 

146386

13.2

6.9

10.3

*USNM 

1W387

6.7 

3.6 

6.1 

0.7

.10 

.91 

1.70

1L18GR16

Dimensions (mm):

Diameter (D) __________ 22

Height of last whorl (H) __ 12.5

Width of last whorl (W) __ 13.5

Width of umbilicus (U) ___ __ 

Proportions:

U/D ________________ __

W/D ________________ .61 .78

W/H _______________ 1.08 1.49

1 USNM 146386 and L18GR16 are from UA loc L18.

2 146387 is from UA loc. L77. All specimen numbers beginning with 

the letter L in this report are University of Arkansas specimens.

Material studied. Hypotypes USNM 146385- 

146387.

Occurrence. Hale Formation, Cane Hill Member, 

USGS localities 19701-PC, 19981-PC (1 specimen each) and UA localities L18 (2 specimens), 

L61 (1 specimen), L77 (2 specimens), Washington County, Ark.

Genus HUDSONOCERAS Moore, 1946 

Hudsonoceras moorei Quinn and Saunders

Plate 1, figures 12-16, text figures 4A, B

Hudsonoceras moorei Quinn and Saunders, 1968, p. 398-400, 

pi. 57, figs. 7-13, text fig. 1.

Diagnosis. Narrow, discoidal conch with gently 

convex venter and flanks bearing shallow groove 

at either side just dorsad of ventrolateral shoulder; surface ornament of fine revolving lirae 

crossed by sinuous transverse lirae forming fine 

reticulate pattern. External suture with broad ventral lobe, and its prongs wide and bluntly pointed.

Description. Discoidal conch having diameter 

about four times width; whorl section subelliptical in immature shell with rounded ventrolateral 

shoulders and convex flanks, becoming subrectangular in maturity with subangular ventrolateral 

shoulders and nearly flat (very gently convex) 

flanks. Shallow groove, whose boundaries are not 

well defined, occurs on each outer flank adjacent 

to ventrolateral shoulder; umbilical shoulder subangular. Diameter of umbilicus about one-sixth 

that of shell; umbilical wall very slightly convex, 

sloping rather steeply inward at angle of roughly 

120° to flank.

Surface sculpture of fine longitudinal lirae separated by subequal to slightly wider interspaces 

best developed over venter and outer flanks, crossed 

by fine transverse growth lirae that curve anteriorly to form ventrolateral salient over ventroFIGURE 4. Hudsonoceras 'moorei 

Quinn and Saunders, incomplete external sutures. A, 

From fragment of a phragmocone (USNM 146399), X 5, 

from UA loc. L18. B, Fragment (USNM 146398), X 5, 

from UA loc. L77.

lateral groove, indistinct in ventral region, forming fine reticulate pattern on some specimens. On 

one specimen (USNM 146397) longitudinal lirae 

are spaced three per millimeter on venter and in 

band 1 mm wide on flanks adjacent to umbilical 

shoulder, five per millimeter in band 1 mm wide 

on flanks just outside of first band, and six to 

seven per millimeter and very faint where preserved on central and outer parts of flanks. No 

transverse constrictions seen.

External suture (shown in fig. 4 from two fragmental specimens) has broad ventral lobe that 

possesses rather evenly rounded median saddle, 

resembling somewhat that of Gonioloboceras ; 

prongs of ventral lobe rather wide, slightly asymmetrical, and bluntly pointed. First lateral saddle 

broadly and rather evenly rounded, slightly subspatulate. First lateral lobe has rather sigmoidal 

ventrad side; dorsad side convex, curving into 

broader asymmetric second lateral saddle that 

crosses umbilical shoulder to short, rather bluntly 

pointed umbilical lobe located near middle of umbilical wall.

L-61-7

Dimensions (mm):

Diameter (D) __________________ 25.7 

Height of last whorl (H) __________ 12.8 

Width of last whorl (W) __________ 6.2 

Width of umbilicus (U) ___________ 4.1

Proportions:

U/D ________________________. 

W/D ________________________. 

W/H _______________________

1 Incomplete and estimated.

.16

.24 

.49

USNlt 

H6397

11.7 

5.0 

3.5

.16
A10 CONTRIBUTIONS TO PALEONTOLOGY

Discussion. The above diagnosis and description is based upon the recently published original 

description of this species, as well as the writer's 

previous study of part of Professor Quinn's material. Specimens from the type locality in the heart 

of Fayetteville, Ark., have not been examined by 

the writer. Quinn and Saunders designated a holotype of this species but called all of the rest of 

their material "figured specimens" and "topotypes." 

As some of the figured specimens contributed 

unique fragments of information to the original 

description and as all of the specimens are germane to their concept of this species, all should 

be considered paratypes. These figured specimens 

from the Country Club locality (L61), 3 miles 

south of Fayetteville, called "topotypes" in the 

plate descriptions, probably are a little too remote 

from the type locality to be bon fide topotypes, 

but they are paratypes.

The shells most similar to this species are Hudsonoceras proteum (Brown) and H. onuitmn 

(Foord and Crick), as pointed out by Quinn and 

Saunders (1968, p. 399). These species have 

conches similar to one another, but the suture of 

H. ornatum differs particularly in the broadly 

sloping sides of the ventral lobe. Direct comparison of the Arkansas species with Irish specimens 

of H. proteum shows both species have similar 

involute discoidal shells with surface sculpture 

predominantly of fine longitudinal lirae, and roughly similar external sutures. The longitudinal lirae 

of H. proteum, like those in H. moorei, are fairly 

coarse and few in number on the venter and immediately outside the umbilical shoulder. They are 

finer and more closely spaced over the flanks. H. 

proteum differs from H. moorei, however, in its 

slightly wider conch, more rounded venter, lack of 

shallow grooves flanking the ventrolateral zones 

and by presence of a slightly raised rim at the 

umbilical shoulder. All the elements of the ventral 

lobe of H. proteum are narrower than those in 

H. moorei; the outline of the median saddle of 

this lobe is subtrapezoidal in H. proteum, instead 

of being regularly arched as in H. moorei. Also, the 

first lateral saddle in H. proteum is narrower and 

more spatulate than in H. moorei.

Five specimens of H. moorei, most of them fragmental, were studied.

Figured specimens. Paratypes, USNM 146397- 

146399, L-61-7.

Occurrence. Hale Formation, Cane Hill Member, UA Iocs. L61 South Mountain (2 specimens),

L18 Kessler Mountain (2 specimens), and L77 Cane 

Hill (1 specimen), Washington County, Ark.

Genus CYMOCERAS McCaleb, 1964

Cymoceras McCaleb, 1964, p. 236.

Type species. Cymoceras miseri McCaleb, 1964 

[=Homoceratoides cracens Gordon, 1965 (1964 

imprint)], by original designation.

This genus includes involute, lenticular shells 

bearing rounded venters and an ornamentation of 

low, gently rounded, broad sinuous transverse 

costae. The costae are dichotomous and divide just 

inside the midflank on most shells. They form 

broad low salients over the ventrolateral zones and 

a moderately shallow ventral sinus. The eight-lobed 

suture has symmetrical to slightly asymmetrical, 

fairly long pointed lobes and asymmetrical rounded 

spatulate lateral saddles.

The type species, C. miseri McCaleb, is similar 

to "Glyphioceras" divaricatum Hind (1905, p. 

114) from the Upper Carboniferous of Great Britain, and the two species appear to be congeneric. 

"G." divaricativm is referred by European paleontologists, following Bisat (1924, p. 113), to the 

genus Homeceratoides; the type species of which 

is H. prereticufatus Bisat (1924, p. 112, 113, pi. 1, 

fig. 3), by original designation Gordon (1964, 

p. 241) notwithstanding.

According to Bisat (1924, p. 112), H. prereticulatus has a subacute fastigiate venter, and the costae, much narrower than in "G." divaricatum, are 

"di-, tri-, or even quadri-chotomizing at the umbilical edge" at 7 mm diameter; the dichotomizing 

point moves from the umbilicus up onto the flanks 

with growth. The suture is not known in H. prereticulatus, which prompted Miller and Owen (1939, 

p. 160) to remark that only the type species could 

be referred to Homoceratoides with certainty.

The lack of anything resembling a subacute 

fastigiate venter in any Arkansas specimens, except for one cited by Gordon (1964, p. 241), in 

which the acute venter was believed to be caused 

by crushing, and the different width and shape of 

the sinuous ramifying costae suggest thr.t Cymoceras deserves recognition as a genus distinct from 

Homoceratoides, certainly until something is known 

about the suture in Homoceratoides. The new species described below has the characteristic sculpture of Cymoceras on the early whor1 -* of the 

phragmocone, but the sculpture becomes faint and 

disappears on the later whorls.

McCaleb (1964, p. 236) suggested that C. miseri 

might be ancestral to Neodimorphoceras, and this 

seems quite reasonable after examining young spe-
AN EARLY RETICULOCERAS ZONE FAUNA All

FIGURE 5. Cymoceras adonis n. sp. A-C, front, side, and 

opposite side views of a paratype (USNM 146395), x 1> 

from USGS loc. 22012-PC.

cimens of N. texanum (Smith); some young specimens were illustrated by Miller and Downs (1950a, 

p. 200-202, pi. 33, text fig. 4).

Cymoceras adonis n. sp.

Plate 1, figures 19-22, 25, 26; text figures 5A-C, 6A-F

Homoceratoides (sic) sp. Clardy, 1962, p. 106, pi. 1, fig. 4.

Diagnosis. Moderately large, involute, subdiscoidal, rounded conch bearing rather flat, sinuous, 

dichotomous, transverse costae on early whorls of 

phragmocone that die out on later whorls. Suture 

bears long, pointed, slightly asymmetrical lobes and 

strongly spatulate saddles.

Description. Conch lenticular, subdiscoidal; 

convex venter rounding without break into gently 

curved flanks (text fig. 5A). Whorl in adult 

phragmocone about three-quarters as wide as high; 

greatest width about one-sixth to one-fifth diameter of shell; umbilical shoulder subangular in 

immature shells as much as 20 mm diameter, shoulder becoming gently rounded and ill defined on 

mature phragmocone; umbilical wall well rounded. 

Sculpture consists of flat, slightly sinuous, gently 

convex, transverse lamellae, slightly raised on orad 

edge, with narrow interspaces. Transverse lamellae 

form very shallow, broad, orad bow on inner 

flank, and broad, shallow, ventrolateral salients 

and intervening ventral and lateral sinuses between bows and salients; visible on internal mold 

(pi. 1, fig. 22). Lamellae bifurcate along line approximately following dorsad side of first lateral 

lobe of suture. At shell diameter of 20 mm, approximately seven flat costae occur within a space of 

5 mm along venter. At diameters from 25 to 30 

mm, costae begin to become faint, and they die 

out at a diameter of 40 mm or slightly more; mature part of phragmocone smooth, as seen in several patches of shell on holotype.

External suture in adult consists of rather 

broad ventral lobe possessing prominent long asymmetrical prongs with points slightly dorsad of center; median saddle subtriangular; sides of ventral 

lobe diverging orad, slightly sigmoidal (fig. 6B, 

E). First lateral saddle deep, rather narrowly 

rounded, spatulate. First lateral lobe slightly narrower than first lateral saddle, sides gently convex, 

pointed tip curving slightly dorsad. Second lateral 

saddle curving asymmetrically and gently across 

umbilical shoulder into umbilicus.

Paratype Holotype Paratypea

146395

52.5

30.5

22.2

Dimensions (mm) : 

Diameter (D) 

Height of last whorl

(H) .__ ______ 

Width of last whorl

(W) ________ . 

Width of umbilicus

(U) ._ _________ 210.0 

Proportions :

U/D ____________ .19 

W/D ___________ .42 

W/H ___________ .73

USNM 

146390

48.4

26.2

20.0

210.0

.22 

.41 

.76

USNM

24.6

13.4

13.3

3.6

.15

.54 

.99

USNM USNM 

146391

22.3

14.0

11.8

3.7

.17 

.53

.84

7.0 

3.5 

5.9 

2.3

.33

.84

1.69

1 Paratype USNM 146395 is from USGS loc. 22012-PC and the rest 

are from UA loc. L77.

2 Approximate.

Cymoceras adonis belongs in the group of "Glyphioceras" divaricatum Hind which has flattened 

sinuous riblets that bifurcate about half way between the umbilical shoulder and midventer. The 

suture of Hind's species, Homoceratoides divaricatus as illustrated by Bisat (1924, pi. 10, fig. 10), 

is similar to that of Cymoceras adonis but has 

shorter, stouter lobes that are a little more sym-
A12 CONTRIBUTIONS TO PALEONTOLOGY

E

FIGURE 6. Cymoceras adonis n. sp. A, C, Cross sections of a paratype (USNM 146392), x 1%, X 5. B, External suture 

of the holotype (USNM 146390), x 2, where H=23.3 and W = 19.6 mm. D, External suture of an immature paratype (USNM 146393), x 5, where D=6.5, H=3.1, and W=5.5 mm. E, Suture of a paratype (USNM 146394), x 1, 

where H=21 and W = 19.5 mm. F, External suture of a paratype (USNM 146391), x 4, where H=6.5 and W=:8.5 

mm. A-D and F are from UA loc. L77; E is from UA loc. L14.

metrical than those of C. adonis. Clardy (1962, p. 

106, pi. 1, fig. 4) figured one of the paratypes of 

this species as Homoceratoides (sic). Another specimen, e,n apparently smooth, large internal mold, 

figured by Clardy (1962, pi. 1, fig. 3) as an undetermined genus, may also belong here.

A recently described Arkansas species of this 

group is Cymoceras miseri McCaleb 1964 [= Homoceratoides cracens Gordon 1964], In that species the lobes of the suture are shorter and wider 

than in C. adonis, and the dichotomous transverse 

costae continue on to the body chamber in mature 

shells, instead of becoming faint and dying out 

fairly early on the phragmocone. C. miseri occurs 

stratigraphically higher than C. adonis and is presumably a descendant of it. The phylogenetic 

change, however, from long to short sutural lobes 

and from faint to moderately strong adult sculpture, seems to be diametrically opposite to what 

one might normally expect in the evolution of a 

phylogenetic stock.

Types. Holotype, USNM 146390; paratypes 

USNM 146391-146395, UA L77CH.

Occurrence. Hale Formation, Cane Hill Member, UA Iocs. L77 (holotype and 11 paratypes) 

Cane Hill, L14 (paratype) Fayetteville; USGS loc. 

22012-PC (paratype) Mount Sequoyah, Washington County, Ark.

Reticuloceras tiro n. sp.

Plate 2, figures 1-13, 35, text figure 1A-D

Diagnosis. Reticuloceras possessing moderately 

involute subspherical conch; venter broadly 

rounded, crossed by shallow sinuous transverse 

lirae and subcontinuous fine faint longitudinal 

lirae. Ventral lobe of mature suture has moderately long prongs with subparallel sides; first lateral lobe mamillate.

Description. Conch narrowly subspherical; 

venter rounding broadly into steeply sloping 

flanks; widest part of shell at narrowly rounded 

umbilical shoulder; umbilical wall strongly convex; 

diameter of umbilicus about one third that of 

shell (fig. 7A, B).

Conch ornamented by approximately 25 narrow, 

unequal, transverse nodes per volution along umbilical shoulder, most of which cross umbilical wall 

on early whorls but become faint on later whorls. 

Sinuous transverse lirae cross flanks and venter 

and arise directly or bifurcate from nodes at or 

near umbilical shoulder; some single lirae intercalated between those arising from nodes. Transverse lirae shallowly sinuous have wider interspaces and form short faint orad bow near umbilical shoulder, wider sinus over each flank, orad bow 

over each ventrolateral zone, and fairly narrow 

ventral sinus; nine to 10 transverse lirae within 

space of 2 mm along venter; approximately three 

transverse growth constrictions per volution, deep-
AN EARLY RETICULOCERAS ZONE FAUNA A13

FIGURE 7. Reticuloceras tiro n. sp., cross sections and 

sutures. A, B, Cross sections of a paratype (USNM 

146402), X 5, x IVz, C, External suture of a paratype 

(USNM 146405), x 10, where D=4.8, H=1.9, and 

W=4.0 mm. D, External suture of a paratype 

(USNM 146401), X 5, where D = 12.5, H=5.7, and 

W=9.2 mm. USNM 146401 and 146402 are from UA 

loc. L77; USNM 146405 is from UA loc. L61.

est on flanks. Longitudinal lirae, much weaker 

than transverse lirae, tiny longitudinal granules 

occurring at intersections with transversals; transverse lirae indistinct over interspaces.

Suture (fig. 1C, D) has rather short, broad ventral lobe, its sides diverging slightly orad and concave outward, terminating in rather short, bluntly 

pointed prongs; median saddle with short central 

projection over siphuncle; first lateral saddle 

rounded spatulate; first lateral lobe slightly wider, 

with evenly convex sides, bluntly pointed; second 

lateral saddle broadly asymmetrical; umbilical 

lobe short, broad, pointed. Internal suture not 

known.

Paratypes Holotype Paratypes

Dimensions (mm) : 

Diameter (D)

Height of last whorl (H) __ 

Width of last whorl (W) _ 

Width of umbilicus (U)

Proportions. 

U/D

W/D

W/H

1 USNM 146401 is from UA loc 

2 USNM 146404 and 146405 are

L18GR 

15.2

_ 7.4 

_ 10.5 

4.8

.32

.70

1.43

L77. 

from UA

1 USNM USNM USNM 2 USNM 

146401 146400 146404 146405

13.2 11.5 9.0 5.3 

6.0 5.0 4.2 2.0 

9.7 8.3 6.8 3.9 

4.7 4.0 3.6 2.7

.36 .34 .40 .51 

.73 .72 .75 .74 

1.62 1.66 1.62 1.95

loc. L61.

Discussion. Some variation is shown by the 17 

designated paratypes and 22 other specimens of 

Reticuloceras tiro collected from four Washington

County localities, particularly in development of 

nodes in immature shells, in spacing of the transverse lirae, and in the development of granules 

on the lirae. Some shells have as few as seven 

transverse lirae per 10 mm along the venter at 

diameters of 10 to 15 mm; the granules are very 

tiny, and the longitudinal lirae in the interspaces 

are invisible. Venters of some internal molds of 

phragmocones have short longitudinal depressions, 

which indicate that at least some individuals of 

R. tiro possessed an intraventral ridge.

Normally, young shells, from 3 to 5 mm in 

diameter, are rather barrel shaped and bear relatively strong umbilical nodes. USNM shells, from 

a locality near the now defunct settlement of 

Thompson, Madison County, Ark., are generally more 

involute at a diameter of 5 mm, and the nodes are 

weaker. These specimens, however, are regarded 

as constituting only a local variant of the typical 

form.

The most similar species to Reticuloceras tiro 

seems to be R. compression Bisat and Hudson, from 

the base of the Lower Reticuloceras (RJ Zone in 

England. In R. compressum the width of the conch 

is one-half the diameter (at 16-mm diam) whereas 

in R. tiro the width is almost three-quarters the 

diameter.

Immature specimens of Branneroceras semiretia 

(McCaleb) might be confused with R. tiro; frit, 

shells of B. semiretia are more evolute, with flatter 

venters in the immature phragmocone, and have 

stronger nodes and logitudinal iirae, and coarser, 

more widely spaced, transverse lirae.

Types. Holotype USNM 146400; paratyp^s 

USNM 146401-146406, additional paratypes in 

University of Arkansas collection.

Occurrence. Hale Formation, Cane Hill Member, UA Iocs. L77 (holotype, 7 paratypes) Cane 

Hill, L61 (10 paratypes, 5 others) South Mountain, L18 (2 specimens) Kessler Mountain. Probable Prairie Grove Member, UA loc. L62 St. Joseph 

Cemetery, Washington County, Ark.

Reticuloceras? wainwrighti Quinn

Plate 1, figures 23, 24; plate 2, figures 14-19, 21-24; text 

figure %A-D

Reticuloceras wainwrighti Quinn, 1966, p. 14-19, text figs. 

1A-C, G, 3, 4.

Diagnosis. Thick discoidal conch with rounded 

venter becoming medially subacute in old age; 

umbilical shoulder subacute, without nodes in 

early stages; diameter of umbilicus equal to about
A14 CONTRIBUTIONS TO PALEONTOLOGY

D

FIGURE 8. Reticuloceras? wainwrighti 

Quinn. A, B, Cross sections of a hypotype (USNM 146460), x 1%, X 5. C, 

External suture of hypotype (USNM 

146457), x 10, where D=7.3 mm. D, 

External suture of the holotype after 

Quinn, x 2%. A-C are from UA loc. 

L61.

one-fourth that of shell. Sculpture of sickle-shaped 

transverse threads locally bunched on umbilical 

shoulder; faint ventrolateral sulci present in some 

mature shells. Suture contains ventral lobe of moderate length having narrow straight pointed prongs.

Description. Conch thick discoidal, moderately 

involute; venter and ventrolateral zones well 

rounded during most of growth, venter .subacute 

in old age; flanks gently convex; widest part of 

shell at subacute to narrowly rounded umbilical 

shoulders; umbilical walls gently convex. Cross section (fig. 8A, B) shows early whorls planorbitally 

coiled for about 4^ volutions, widening for about 

two volutions, then adding more height in later 

volutions.

Surface of conch ornamented by fine, raised, sinuous, transverse lirae of approximately equal 

strength over venter, but of unequal strength and 

locally bunched near umbilical shoulder; interspaces generally wider than lirae; seven to 10 

lirae within space of 2 mm along venter at diameters of 15 to 20 mm. Lirae continue closely .spaced 

across umbilical wall, some of them more elevated 

than others; on inner flanks lirae form a shallow 

orad bow with narrower shallow sinus over mid

flanks, more prominent orad bow over ventrolateral 

zones, bounded at either side in some mature .specimens by faint shallow longitudinal sulcus but most 

without sulci. Ventral sinus well rounded, about 2 

mm deep at diameters of 15 to 20 mm, measured 

from farthest orad projection of ventrolateral bows 

in growth lirae. Internal varices approximately follow configuration of transverse lirae; three to four 

varices per volution, but not visible where shell 

surface is preserved.

Suture goniatitid; in immature shells (fig. 8C), 

ventral lobe fairly short, with fairly straight sides 

diverging slightly outward, indented by .small, 

broadly subrectangular, median saddle into two 

short subrounded prongs, each with sharp ventrapicad corner; first lateral saddle slightly asymmetrical and spatulate; first lateral lobe rather evenly 

convex, terminating in blunt point; second lateral 

saddle rather narrow and asymmetrically rounded 

to short, sharp, umbilical lobe. Suture in mature 

shells (fig. 8D) has ventral lobe slightly longer 

than wide, indented to about half its length by 

median saddle with narrow prongs terminating in 

centrally located points. First lateral saddle wider 

than ventral lobe, asymmetrical, rounded. F'rst lateral lobe narrower than ventral lobe, nearly 

symmetrical, simply pointed. Second lateral saddle 

broadly asymmetrical, curving across umbilical 

shoulder into short pointed umbilical lobe.

1 USNM USNM USNM

146455 

Dimensions (mm) :

148406 L61cl77 LeiclSl 146458

Diameter (D)

Height of last whorl (H) ____ 

Width of last whorl (W) ____ 

Width of umbilicus (U) _____ 

Proportions : 

U/D

W/D

W/H

19

8.7 

10.3 

5.0

.26

.54

1.18

7.5 

9.4 

3.8

.25

.62

1.25

4.5 

6.6 

3.0

.30

.66

1.47

F.5

f'.5 

f.O

.35

.65

1.57

6.8

3.0 

4.4 

2.2

.34

.68

1.47

1 The first specimen (USNM 146455) is from UA loc. L18; the rest are 

from UA loc. 161.

Discussion. Occurring with Reticuloceras tiro n. 

sp., in collections from all four localities where 

that species was recorded, are 25 specimens of a 

similar-sized but narrower shell. This shell differs 

from R. tiro in several particulars and was described by Quinn (1966, p. 14) as Reticuloceras 

wainwrighti n. sp. Quinn's holotype, 37 mm in diameter, is considerably larger than any of the specimens studied here. The specimens in this report, 

therefore, serve to illustrate the character? of less 

mature examples of this species, not shown by the 

characters of less mature examples of this species, 

not shown by the primary types. Quinn's holotype 

(UA L99-185) came from a locality not included 

in the present study. His "old age" paratype (UA
AN EARLY RETICULOCERAS ZONE FAUNA A15

L18-9), however, came from one of the localities 

in this report.

Because these R.I wainwrighti shells do not possess longitudinal lirae or umbilical nodes at any 

stage of growth, the writer originally regarded 

them as belonging in Homoceras or some related 

genus. However, some specimens of Reticuloceras 

tiro, particularly at locality L61, approach R.I 

wainwrighti in shape and sculpture, and the possibility that they might represent sexual dimorphs 

of R. tiro was considered but eventually rejected.

Reticuloceras ? wainwrighti and R. tiro should not 

be regarded as variants of the same species because of the following differences between the two 

forms: (1) Immature shells of R. tiro have umbilical nodes; those of R.I wainwrighti do not. (2) 

The conch of R. tiro is somewhat reticulate; that 

of R.I wainwrighti lacks longitudinal lirae. (3) 

The conch of R. tiro is proprotionally wider than 

that of R.t wainwrighti. (4) The umbilicus of 

R. tiro is proportionally larger than that of R.t 

wainwrighti. (5) The early planorbitally coiled 

stage in R. tiro lasts slightly more than three volutions, as against 4V& to five in R.I wainwrighti. 

(6) The ventral lobe of the adult suture of R. tiro 

has slanting sides; that of R.I wainwrighti has 

subparallel sides, except in young specimens.

The gerontic stage of R. ? wainwrighti illustrated 

by Quinn (1966, text figs. IB, C and 4) has a subacute, fastigiate venter. Another specimen from the 

same locality as Quinn's example (UA loc. L18), 

showing an incipient subangular venter, is figured 

here (pi. 1, figs. 23, 24). Quinn (1966, p. 13) believes that this venter in gerontic R.I wainwrighti 

is similar to that in Reticuloceras davisi (Foord and 

Crick) which some paleontologists regard as the 

gerontic form of and therefore synonymous with 

R. reticulatum (Phillips) and he regards this similarity as "inescapable proof" that R.I wainwrighti 

is an American Reticuloceras. Various other ammonoids, however, have subacute to acute venters 

at maturity or in old age, including the type species of Homoceratoides, H. prereticukitum Bisat, 

of which, unfortunately, the suture is not known.

The gerontic specimen figured in this report 

(pi. 1, figs. 23, 24) also exhibits faint longitudinal 

sulci just within the ventrolateral shoulder. Similar faint ventrolateral sulci are shown also on another figured specimen (pi. 2, fig. 16). These faint 

sulci bound on the ventral side the orad bow of 

the transverse lirae over the ventrolateral zones 

in the specimen cited immediately above. The faint 

sulci cannot be discerned on internal molds except

in the one living chamber figured (pi. 1, figs. 23, 

24). This character apparently was developed 

rather late in growth; it was variable and probaably absent on some specimens.

Less mature shells of this species can be confused with Weideyoceras matheri (Gordon) from 

the upper part of the Hale Formation, but this species is a little narrower and more involute, has 

much finer and more closely spaced growth lirae, 

and the first lateral lobe of its suture is narrower 

and more sharply pointed in young shells.

Types. Hypotypes, USNM 146455-146460, UA 

L61c-177, 191.

Occurrence. Hale Formation, Cane Hill Member, 

UA Iocs. L18, L61, L77; Prairie Grove Member (?) 

UA loc. L62; Washington County, Ark.

Reticuloceras? sp.

Plate 1, figures 17, 18; text figure 9

A single incomplete specimen is widely umbilicate, with a prominent umbilical shoulder, sculpture of sinuous crenulated transverse lirae, and a 

gastrioceran suture. It does not fit easily into ary 

described genus, but seems to be closest to Reticuloceras tiro n. sp., although it is much more evolute.

This specimen is an incomplete internal mold of 

an evolute phragmocone which has reached a diameter (slightly distorted) of 41 mm. The venter is 

well rounded, the ventrolateral zones subdued; tl ^ 

venter rounds into the flanks which slope outward 

at an angle of about 30° to the vertical axis of th°. 

shell. The umbilical shoulder is prominent, subangular, and the umbilical wall is nearly flat. No welldefined growth constrictions can be seen, but here 

and there the flanks near the umbilical shoulder 

are dimpled by what seem to be vestiges of transverse constrictions that may have become indistinct 

at this diameter. On the venter, near its orad end, 

are preserved two small patches of shell showing 

a surface sculpture of minutely wavy transverse 

lirae, with interspaces wider than the lirae; six of 

these lirae occur within the space of 2 mm. They 

are strongly oblique and outline one side of a moderately deep ventral sinus and a prominent bow 

orad over the ventrolateral zone. The crenulations 

of the lirae line up in a rude longitudinal pattern, 

somewhat reminiscent of Nuculoceras, though not 

definitely longitudinally lirate.

The external suture (fig. 9) has a ventral lobe, the 

prongs of which are fairly straight on the dorsrd 

side and curved on the ventrad side where they
A16 CONTRIBUTIONS TO PALEONTOLOGY

FIGURE 9. Reticuloceras? 

sp., external suture from 

the unique specimen (USNM 146388), X 2, 

where H = 10 and W= 

21 mm, from UA loc. 

L18.

form a subtriangular median saddle of moderate 

depth. The first lateral saddle is asymmetrically 

curved dorsad and spatulate. The first lateral lobe 

is rather symmetrical and mamillate and has convex sides. The second lateral saddle curves asymmetrically to the short sharp umbilical lobe.

Dimensions, in millimeters. Diameter (D) 36, 

height of last whorl (H) 11.5, width of last whorl 

(W) 23, and width of umbilicus (U) 20. These 

give the following proportions: U/D=0.56, W D 

=0.64, and W/H=2.0.

Figured specimen. USNM 146388.

Occurrence. Hale Formation, Cane Hill Member, UA loc. L18, Kessler Mountain, Washington 

County, Ark.

Genus BRANNEROCERAS Plummer and Scott, 1937 

Branneroceras semiretia (McCaleb)

Plate 2, figures 20, 25-30; text figures 10A-C, 11

Retites semiretia McCaleb, 1964, p. 234, 235, pi. 1, figs. 1-5, A.

Diagnosis. Moderately evolute Branneroceras 

having rather primitive suture in which first lateral lobe and prongs of ventral lobe are wider and 

median saddle shorter than in B. branneri 

(Smith).

Description. Conch thickly discoidal (fig. 10A, 

B), narrowing very slightly with growth, evolute; width of umbilicus roughly one-half shell diameter; U/D ratio tending also to diminish slightly with growth. Venter rounded, somewhat flattened 

in immature and early mature phramocone, more 

elevated in mature shell; flanks well rounded in 

immature phragmocone with greatest width near 

umbilical shoulder, less rounded in mature conch 

with greatest width approximately at shoulder.

Ornamentation consists of 27 to 35 radial to 

slightly protractive elongate nodes on each immature whorl, extending into riblets on later whorls; 

nodes and riblets giving rise to sinuous transverse 

lirae forming shallow sinus on each flank; promiFIGURE 10. Branneroceras semiretia (McCaleb). A, B, Cross section of a hypotype 

(USNM 146464), x 1%, X 5 from USGF 

loc. 19981-PC. C, External suture from a 

hypotype (USNM 146462), x 2%, where 

D=23, from UA loc. L62.

nent nearly linguiform orad bow on each ventrolateral zone and rather deep U-shaped ventral sinus 

between. As many as four moderately deep growth 

constrictions commonly occur on each whcrl, paralleling configuration of transverse lirae. Longitudinal sculpture consists of numerous lirae, with interspaces wider than lirae, forming reticulate network with transverse Jirae; longitudinal lirae 

tending to be a little less strong over ventral sinus 

and inner flanks. Shallow longitudinal groove at 

either side of ventral sinus in some specimens.

External suture (fig. 10C) with subrectangular 

ventral lobe, having sides nearly straight but very 

slightly sigmoidal, its prongs of moderate width, 

slightly asymmetrical with points a little to dorsad 

side, divided to not quite one-half of its length by 

inverted-goblet-shaped median saddle. First lateral 

saddle very slightly asymmetrical, narrowly arched. 

First lateral lobe also very slightly asymmetrical 

and a little wider than first lateral saddle, rather 

bluntly pointed, curving into second lateral saddle 

which extends rather straight across shoulder to 

short, pointed umbilical lobe.

A variant, represented by a rather mature incomplete phragomocone, has a considerably wider first 

lateral lobe (fig. 11).
AN EARLY RETICULOCERAS ZONE FAUNA A17

FIGURE 11. Branneroceras semiretia (McCaleb), 

variant. External suture from a mature phragmocone (USNM 146407), x 5, where H=9.0 and 

W = 15.1 mm, from UA loc. L77.

USNM USNM USNM USNM 

146461 146462 146464 146463

Dimensions (mm):

Diameter (D) _______ 30.5 26.0 a !8 15.0 

Height of last whorl (H) 11.0 8.3 6.8 4.7 

Width of last whorl (W) 215.2 2 15.3 211 9.3 

Width of umbilicus (U) __ 13.8 12.0 7.6 7.2

Proportions:

U/D _____________ .45 .46 .43 .48 

W/D _____________ .50 .59 .61 .62 

W/H _____________ 1.36 1.84 1.62 1.98

1 Approximate.

2 Twice the half width. For locality data on these specimens see 

descriptions of figures.

Discussion. B. semiretia is one of the more common ammonoids in the middle part of the Hale 

Formation; there are 150 specimens in the collections under study. In his original description of this 

species, McCaleb (1964, p. 233) based a new genus, 

Retites, on it, which is characterized principally 

by its more primitive suture. In the writer's opinion, the characters that differentiate this species 

from Branneroceras bramieri (Smith) are not 

sufficient to warrant erecting a new genus, separate and distinct from Branneroceras, of which 

Retites is. here considered a synonym.

Branneroceras bramieri differs from B. semiretia 

in having a slightly narrower conch which is consistently subdiscoidal, more regular and consistent 

lirae on the venter, and the prongs of the ventral 

lobe and the first lateral lobe are narrower; the 

ventral lobe is divided to about three-fifths its 

length by the median saddle compared to a little 

less than one-half in B. semiretia. B. semiretia, no 

doubt was ancestral to B. bramieri, as indicated by 

McCaleb (1964, p. 233), and was the earliest known 

representative of the Pennsylvanian ammonoid 

family Schistoceratidae.

Although McCaleb (1964, p. 234) said the name 

semiretia is derived from the Latin retia meaning 

"netted," the Latin Dictionary discloses no participle nor adjective of this spelling. Instead, retia 

is shown as a feminine noun meaning "net." For 

this reason the specific name semiretia is here regarded as a noun in apposition, and the ending 

does not change when transferring it to Branneroceras, a neuter generic name.

Types. Hypotypes USNM 146461-146464.

Occurrence. Hale Formation, Cane Hill Member* 

UA Iocs. L14, L18(?), L61, L77, and USGS Iocs. 

19702-PC, 19981-PC, and 22012-PC; Prairie 

Grove Member(?), UA Iocs. L59, L62, and USGS 

loc. 19701-PC; Washington County, Ark.

Genus STENOPRONORITES Schindewolf, 1934 

Stenopronorites quinni n. sp.

Plate 2, figures 31-34; text figures 12A, B

Diagnosis. Pronoritid having rounded venter 

devoid of ribs up to whorl heights as much as 40 

mm and perhaps more. Five lateral lobes occur on 

external suture.

Description. Conch discoidal, with flat sides, a 

well-rounded venter, and rounded umbilical shoulder. Early whorls are planorbitally coiled, wider 

than high; but at a diameter of 10 to 15 mm, 

whorls increase markedly in height and shell assumes typical pronoritid shape. Phragmocones, SO 

to 40 mm in height, show no signs of ventral ribbing. Living chambers not known.

Suture at whorl height of 10 mm (fig. 125) has 

ventral lobe and five lateral lobes on each flank, decreasing in height gradually from second later;?.! 

lobe, plus two short umbilical lobes. Ventral 

lobe trifid; first lateral lobe moderately wide ard 

short and rather shallowly divided into two short 

prongs. Other lateral lobes asymmetrical, slightJy 

club shaped, and pointed. Umbilical lobes rounded, 

short; inner one incipient.

B

FIGURE 12. Stenopronorites quinni n. sp. A, Incomplete cross section of a paratype (USNM 146466), 

X 1%. B, External suture of the holotype (USNM 

146465), x 4, where H=9.8 and W=6.8 mm. Both 

specimens are from UA loc. L77.
A18 CONTRIBUTIONS TO PALEONTOLOGY

Paratypes

1USNM 2USNM 

146467 146466

Dimensions (mm):

Diameter (D) ________ __ 25.1 

Height of last whorl (H) __ 31.8 13.4 

Width of last whorl (W) __ 17.8 8.3 

Width of umbilicus (U) __ __ 5.5

Pi-oportions:

U/D _______________ __ .22 

W/D _______________ __ .33 

W/H _______________ .56 .62

1 USNM 146467 is from UA loc. L1S.

2 USNM 146465, 146466 from UA loc. L77.

Holotype

"U.SNM 

146465

9.5 

6.8

.71

Discussion, This species is known from a number of incomplete phragmocones in Hale Formation 

collections. Fifteen fragmental specimens occur in 

the collections under study. The holotype consists 

of part of two volutions of a phragmocone.

Stenopronorities quinni n. sp. differs from S. arkansiensis (Smith), which occurs in the Bloyd 

Shale and Atoka Sandstone, by having a more primitive suture and, so far as is known, a conch without marked ventral ribbing. A specimen of S. arkansiensis from the Witts Springs Formation on Gaither Mountain, Boone County, Ark., has 

six lateral lobes at a whorl height of 9 mm. The 

bifid first lateral lobe of S. arkansiensis is a little 

more deeply divided; the saddle reaches half the 

length of the lobe in some specimens, whereas in 

S. quinni it does not exceed two-fifths of the length 

of the lobe. Because no living chambers of S. 

quinni are known, it cannot be claimed that this 

species is completely devoid of ventral ribbing, but 

specimens of S. arkansiensis examined in this study 

commonly have developed ribbing by a whorl 

height of 30 mm. It would seem that S. quinni is a 

somewhat more primitive pronoritid directly ancestial to S. arkansiensis.

The species most closely related to <S. quinni 

seems to be Uralopronorities minis Librovitch (in 

Ruzhentsev, 1949), from beds of Namurian Age 

in the Ural Mountains, U.S.S.R. The writer regards Uralopronorites Librovitch as a synonym 

of Stenopronarites. The Russian species has a 

rounded venter and a 20-lobed suture that is approximately in the same stage of evolutionary development as that of S. quinni. Although the internal suture of S. quinni has not been seen, examination of whorls broken partly along septa indicate that the Cane Hill species has a suture with a 

total of 20 lobes. Differences between the two species are relatively minor. Stenoproncxrites minis 

has a less convex venter and a wider, more asymmetrically and shallowly notched first lateral lobe 

than S. quinni.

Types. Holotype USNM 146465, paratypes 

USNM 146466, 146467. Other paratypes in UA collection.

Occurrence. Hale formation, Cane Hill Member, 

UA Iocs. L77 (holotype and 4 paratypes) Cane Hill, 

L18 (3 paratypes) Kessler Mountain, L61 (3 specimens) and USGS loc. 19702-PC (1 fragment) 

South Mountain; Washington County, Ark. Prairie 

Grove Member (?) UA loc. L62 (3 specimens) St. 

Joseph Cemetery, Washington County, Ark.

REFERENCES CITED

Bisat, W. S., 1924, The Carboniferous goniatites of the north 

of England and their zones: Yorkshire Geol. Soc. Proc., 

v. 20, pt. 1, p. 40-124, pis. 1-10.

Clardy, B. F., 1962, Goniatite cephalopod faunas from the 

Hale Formation: Compass, v. 39, no. 3, p. 103-109, 2 pis., 

1 text fig.

Cox, E. T., 1857, Paleontological report of the Coal Measures

Mollusca: Kentucky Geol. Survey Kept. no. 3, p. 555-576,

pis. 7-10 [1858]. 

Easton, W. H., 1943, The fauna of the Pitkin Formation of

Arkansas: Jour. Paleontology, v. 17, no. 2, p. 125-154,

pis. 21-24, 1 text fig.

Gordon, Mackenzie, Jr., 1964, Carboniferous cephs.lopods of 

Arkansas: U.S. Geol. Survey Prof. Paper 467, 322 p., 

32 pis., 96 text figs., 11 tables [1965].

Hind, Wheelton, 1905, Notes on the homotaxial equivalents 

of the beds which immediately succeed the Carboniferous 

limestone in the west of Ireland: Royal Ir;sh Acad. 

Proc., v. 25, sec. B, no. 4, p. 93-116, pis. 3-6.

Librovitch, L. S., 1938 Kamennougol'nye ammonei s yuzhnogo 

ostrova Novoi Zemli [Carboniferous ammonoHs of the 

southern island of Novaya Zemlya]: Vsesoyuznogo Arkticheskogo instituta Trudy, torn 101, p. 47-107, 5 pis., 

13 text figs., Leningrad, (English summary, p 85-104.)

 1957, O nekotorykh novykh gruppakh goriatitov iz 

kamennougornykh otlozheni SSSR: USSR, Vsesoiuznoi 

paleontologicheskoe obshchestvo Ezhegodnik, torn 16, 

1955/56, p. 246-273, 4 pis., 10 text figs.

McCaleb, J. A., 1964, Two new genera of Lower Ponnsylvanian ammonoids from northern Arkansas: Oklahoma Geology Notes, v. 24, no. 10, p. 233-237, 1 pi.

Miller, A. K., and Downs, H. R., 1950a, AmmonoMs of the 

Pennsylvanian Finis Shale of Texas: Jour. Paleontology, 

v. 24, no. 2, p. 185-218, pis. 31-35, 11 text figr.

 1950b, Additional ammonoids from the Mis'sissippian 

Barnett Formation of Texas: Jour. Paleontology, v. 24, 

no. 5, p. 575, 576, pi. 78, 1 text fig.

Miller, A. K., Furnish, W. M., and Schindewolf, O. H., 1957, 

Paleozoic Ammonoidea: in Moore, R. C., ed., Treatise on 

invertebrate paleontology, pt. L (Mollusca 4), New York 

and Lawrence, Kans., Geol. Soc. America and Univ. 

Kansas Press, p. L11-L79, text figs. 1-123.
AN EARLY RETICULOCERAS ZONE FAUNA A19

Miller, A. K., and Moore, C. A., 1938, Cephalopods from the 

Carboniferous Morrow Group of northern Arkansas and 

Oklahoma: Jour. Paleontology v. 12, no. 4, p. 341-354, 

pis. 43, 44, 4 text figs.

Miller, A. K., and Owen, J. B., 1937 A new Pennsylvanian 

cephalopod fauna from Oklahoma: Jour. Paleontology, 

v. 11, no. 5, p. 403-422, pis. 50-52, 5 text figs.

 1939, An ammonoid fauna from the Lower Pennsylvanian Cherokee Formation of Missouri: Jour. Paleontology, v. 13, no. 2, p. 141-162, 4 pis., 9 text figs.

Moore, E. W. J., 1946, The Carboniferous goniatite genera 

Girtyoceras and Eumorphoceras: Yorkshire Geol. Soc. 

Proc., v. 25, pt. 6, p. 387-445, pis. 22-27, 31 text figs.

Plummer, F. B., and Scott, Gayle, 1937, Upper Paleozoic 

amonites in Texas: Texas Univ. Bull. 3701, pt. 1, 516 p., 

42 pis., 87 text figs.

Quinn, J. H., 1963, Stratigraphic position of Eoasianites 

globosus: Oklahoma Geology Notes, v. 23, no. 2, p. 26-28, 

2 text figs.

 1966, Genus Reticuloceras in America: Oklahoma Geology Notes, v. 26, no. 1, p. 13-20, 4 text figs.

Quinn, J. H., and Saunders, W. B., 1968, The ammonoids 

Hudsonoceras and Baschkirites in the Morrowan Series 

of Arkansas: Jour. Paleontology, v, 42, no. 2, p. 397-402, 

pi. 57, 3 text figs.

Ruzhentsev, V. E., 1949, Sistematika i evoliutsiya semeistva 

Pronoritidae Frech i Medlicottiidae Karpinsky: Akad. 

Nauk SSSR, Paleontologicheskii Institut Trudy, torn 19, 

204 p., 17 pis., 88 text figs.

Ruzhentsev, V. E., and others, 1962, Nadotryad AmmonoWea, 

in Ruzhentsev, V. E., ed., Osnovy paleontologii, spravochnik dlya paleontologov i geologov SSSR; [t. 5], Molliuski; golobonogie, I, Nautiloidei, endotseratoidei, aktinotseratoidei, baktritoidei, ammonoidei (agoniatity, goriatity klimenii): Moscow, Akad. .Nauk SSSR, p. 243-424, 

32 pis., 187 text figs.

Schindewolf, 0. H., 1934, Uber zwei jungpalaozoische Cepl alopodenfaunen von Menorca: Gesell. Wiss. Gottingen Abh., 

Math.-phys. Kl., ser. 3, no. 10, p. 155-192, pi. 6, 4 text 

figs.

Yin, T. H., 1935, Upper Paleozoic ammonoids of China: 

Paleontologia Sinica, ser. B, v. 11, pt. 4, 33 p., 5 pis., 

10 text figs.

INDEX

[Italic numbers indicate descriptions and major references']

Ammonoid localities, other_ 

Arkanites relictus __.-.----. 

Atoka Sandstone.__._____.

Page 

A5

5

18

Bashkirian Stage..__.._._.._...._........._........................ 6

Bisatoceras. ._..._____._-....__.___.._._____..._____._._.._______.._ 8

paj/wei____.___......_._._..__.______.___..____.____.__ 3, 4, 5, 8; pi. 1

Bloyd Shale__...._. ..._..........._.... ._._........_...._.. 6,18

Branneroceras. _____________________________________________________ 16

branneri. ___________ _________________________________________ 17

semreKo-----....----_--_-.--.---.-..___---_--..-. 3, 4, 5, 13, 16; pi. 2

Brentwood Limestone Member of Bloyd Formation.-.._-._-.______-__._ 4, 8

Cane Hill.. __________________________________________________ 1, 10, 13, 18

Cane Hill cephalopod localities.______________________________._ __-- 1

Cane Hill .Member of Hale Formation____ 1, 3, 4, 5, 9, 10, 12, 13, 15, 16, 17, 18 

Collecting localities for fauna.___-___--________--______-______-____-- S

Cravenocery.8- __-__-_--_---_-_--_---__-___-___-_____-______-__----__ 8

morrowense.................................................... 6, 8

Cymoceras ..............................^._........................ 10

adonis................................................ 3, 4, 5, 11; pi. 1

miseri......................................................... 10,12

D

Descriptions of species______________________________________________ 5

E 

Eoasianites ________________________________________________________ 5, 6

globosus....................................................... 6

F 

Fayetteville Country Club..________________________________________ 3, 4

Fayetteville Shale._____________________________________________ 3, 4

G

Gastrioceras orientale. _..._._ ________________________________________ 5, 6

sitborientale ..........._..............___._..................... 6

Glaphyrites^....................................................... 5, 6

depressus...................................................... 6

globosus _-_--_-__-_-__________-_---__________-_---__---__-.____ 6

morrowensis.................................................... 6, 8

oblatus............................................... ________ 6, 8

Glyphioceras divaricatum. _-_____-------_--________---____---__---____ 1,0,11

Goniatites nolinensis............................. ____________________ 6, 8

Gonioloboceras...................................................... 9

H 

Hale Formation...... ___ __________________ 4,6, 9, 10,12, 13, 15, 16, 17, 18

Homoceros.... _.___..__.__.__.__.________ .__.__.___._..__.._.....__ 5, 15

Homoceras (H) Zone_____.. _.__....__._ .._______.__._...__.__...__._ 5

Homoceratoides --..---- -__-..___..._-_-.-.___.... ---------.-__----_-- 15

cracews. _______________________________________________________ 10, 12

prereticulatum _ 

prereticulatus- _

moom'-___ -------------____---____-._________________.__. 3, 5, 9; pi. 1

ornatum. --.----.-----___-_---_-________________________._____. 10

profeum__ _____________________________________________________ 10

Kessler Mountain.

Lower Reticuloceras (R) Zone in England. 

Lower Reticuloceras Zone_______________

Page 

4, 10,13, 16, 18

13

5

M

M orrow Sea ___..____--_______--_--_-____-_______-----._-_--------- 1

Morrow Series in United States- _____--_-__________-______-__-_____-- 6

Mount Sequoyah______--________-_---______-_. _____________________ 4, 12

N

Neodimorphoceras _

texanum-.--.

Nueuloceras .- _ _

10

11

15

Pitkin Limestone..________ _________________________________________ 1, 4

Prairie Grove Member of Hale Formation..__________ 1, 3, 4, 5, 13, 15, 17, 18

Pseudoparalegoceras- ________________________________________________ 6

(Phaneroceras) _________________________________________________ 6

R 

Register of localities._...________--_._ _______-__----___-.______----- ^

Reticuloceras.... -____-___--__-___._----___---_-----------_--------- 1

compressum. __._____._.______._.._._..______-_--_._------_____- 5, 13

da»isi_____________________-__-___--_-___.--------_--------_--- 15

heribesti. ___.._._____..._____---_--_--____--_---------_-------- 5

reticulatum....... _______________________________ _____._______-- 15

«ro._ ____________________________________________ 3, 5, i2, 14, 15; pi. 2

Assemblage Zone.________________________-__-_-.-_----._--- 5

Zone.__-_-_-_____________.____________-___----------_--- 6

«>aiMjt'riflM.____-_--__________________________-__-_- 3, 4, 5, i3; pis. 1, 2

sp.-_________-----._______________________-_.___.__---- 3, 5, 15; pi. 1

Ref ites semiretia. _______-_______-_-__-_-_________________----------_ 16

Round Top Mountain___________----_____-_--___----___----------_ 4

Sequoyah Mountain_______________-______--__----------_--------_-- 3

South Mountain____--.___________-__-__-__-----_--------------- 4, 13, 18

Stenopronorites __._____..________..____-___--___.---------_--------- 17, 18

arkansiensis ___..._______...___----_-_--_-_-------------------- 18

gitinw.-._______.______..______------__-----------__----- 3, 5, i7; pi. 2

Stratigraphic setting of the fauna________-_______-__--_-----_--------- 1

Syngastrioceras.........-....---------.-..-----.-------------------- 5, 6,8

globosum. ________-.____-----__------_----__----------- 3, 4, 5, 6; pi. 1

oblotuni- ______-----______-____----___----------------_-------- 6

uralicus ___.___-. -_-_.-____-__-----____--------------------_-_- 6

U

UA (University of Arkansas) localities. _ - 

Uralopronorities mirus-- __.______.__-__

USGS (U.S. Geological Survey) localities.

W

Weideyoceras matheri--.,- 

Witts Springs Formation .

4

18

15

18

A 21

PLATES 1 and 2
PLATE 1

[All figures natural size except as otherwise indicated on plate.]

FIGURES 1 7. Syngastrioceras globosum (Easton) (p. A6).

1-3. Front, side, and back views of hypotype; USNM 146379, from UA loc. L77. 

4-7. Involute form. Enlarged back view and front, side, and back views of hypotype; 

USNM 146382, from UA loc. L61.

8-11. Bisatoceras paynei Gordon (p. A8).

Enlarged front, side, and back views and side view of hypotype; USNM 146385, 

from USGS loc. 19701-PC.

12-16. Hudsonoceras moorei Quinn and Saunders (p. A9).

12-14. Enlarged ventral and side views and a side view of a fragmental paratype;

USNM 146397, from UA loc. L61. 

15, 16. Side and back views of a paratype; USNM 146396, from same locality.

17, 18. Reticuloceras? sp. (p. A15).

Side and ventral views of a fragmental, unique specimen; USNM 146388, from UA 

loc. L18.

19-22, 25, 26. Cymoceras adonis Gordon, n. sp. (p. All).

19-22. Front, side, and back views and enlarged side view of a nearly perfect immature paratype; USNM 146391, from UA loc. L77.

25, 26. Ventral and side views of a larger incomplete phragmocone, the holotype; 

USNM 146390, from UA loc. L77.

23, 24. Reticuloceras? waimvrighti Quinn (p. A13).

A variant. Fragment of a moderately large shell showing shallow ventrolateral sulci; 

USNM 146408, from UA loc. L18.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 613-A PLATE 1

SYNGASTRIOCERAS, BISATOCERAS, HUDSONOCERAS , RETICULOCERA&,

AND CYMOCERAS
PLATE 2

[All figures natural size except as otherwise indicated on plate.]

FIGURES 1-13, 35. Reticuloceras tiro Gordon, n. sp. (p. A12).

1, 2. Enlarged back and side views of small paratype; USNM 146405, from UA loc.

L61. 

3-6, 35. Side and enlarged front, side, and two back views of holotype; USNM

146400, from UA loc. L77. 

7-9. Side and enlarged back and side views of paratype; USNM 146404, from UA

loc. L61. 

10-13. Side and enlarged back, side, and front views of paratype; USNM 146403,

from UA loc. L61.

14 19, 21-24. Reticuloceras? wainwrighti Quinn (p. A13).

14-16, 21, 24. Enlarged front, side, and back views, side view, and enlarged side

view of specimen showing faint ventrolateral sulci; USNM 146406, from UA

loc. L61. 

17-19. Enlarged back, side, and front views of smaller specimen; USNM 146456, from

UA loc. L61. 

22, 23. Enlarged side and front views of larger specimen; USNM 146455, from

UA loc. L18.

20, 25-30. Branneroceras semiretia (McCaleb) (p. A16).

20. Side view of a fairly large hypotype; USNM 146462, from UA loc. L62.

25-28. Enlarged back view, side view, and enlarged side and front views of a "hypotype; USNM 146463, from UA loc. L59.

29, 30. Side and back views of more mature hypotypes; USNM 146461, from USGS 

loc. 19702-PC.

31-34. Stenopronorites quinni Gordon, n. sp. (p. A17).

Side and enlarged ventral, side, and dorsal views of a phragmocone, the holotype; 

USNM 146465, from UA loc. L77.
GEOLOGICAL SURVEY PROFESSIONAL PAPER 613-A PLATE 2

35

RETICULOCERAS, RETICULOCERASt, BRANNEROCERAS, 

AND STENOPRONORITES

 U. S. GOVERNMENT PRINTING OFFICE : 1968 O - 325-387