SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936 

NEW UPPER CRETACEOUS OS REIDAE FROM THE GULF REGION 

ABSTRACT 

Four species of Ostreidae from the Upper Cretaceous of he 

Gulf region are described and figured. Three of the spec es, 

GryP'haea wratheri, Ostrea johnsoni, and Ostrea travisana, are 

new. o8 trea elegantula White, originally described fr~m New Mexico, is here first recorded from the Gulf region. ll 

four of the species are narrowly confined in their verti al 

r1ange and have- more or less extended geographic ranges; t ey 

are therefore useful as index fossils. The zones that the s ecies characterize lie either in the upper part of the Aus in 

chalk or in beds of upper Austin age (Santonian). 

The family Ostreidae is represented in the Upper 

Cretaceous formations of the Atlantic and Gulf 

Coastal Plain by the four genera Ostrea, Gryphaea (in 

the broad sense), Gryphaeostrea, and Ewogyra: and by 

many species, some of which have not yet been described. Three new species, one of Gryphaea and two 

of Ostrea:, are placed on record in this paper; they are 

Gryphaea wratheri, Ostrea travisama, and 0. johnsoni. 

A fourth species, Ostrea elegantula White, not previously identified from the Gulf region, is redescribed, 

and shells from Alabama, more nearly perfect than 

the type material, are figured ; one specimen from 

New Mexico is figured. These species aU occur within 

a relatively narrow stratigraphic range, which is believed to correspond approximately to the Santonian 

division of the Senonian of Europe. 

In Texas Gryphaea wratheri occupies the lowest 

stratigraphic position of the four species under consideration. It occurs in a zone well above the middle 

of the typical Austin chalk in Travis County and has 

been collected in this zone at more or less widely separated localities from Dallas County to Guadalupe 

County, a distance of 250 miles; the zone has an observed maximum thickness of at least 35 feet. In the 

Austin chalk, immediately below this zone, is another 

zone characterized by an abundance of the imprints 

and shells of I noceramu'8 wndulato-plicatus Roemer, 

and in places this species has been observed to range 

upward into the Gryphaea wratheri zone; the lower 

zone is also relatively thin (thickness 50± feet) and 

an even greater known geographic extent than the 

upper zone, having been recognized at numerous localities from the vicinity of Whitewright, Grayson 

County, Tex., to Cow Creek, in southern Kinney 

65752-36-2 

County, Tex., a distance of 450 miles. The well-known 

species Gryphaea au,cella Roemer occurs in great numbers within a few feet above the G. wratheri zone, 

but Roemer's species has a greater vertical range than 

G. wratheri, having been found in considerable numbers at higher levels to a horizon within 20 or 25 feet 

of the top of the Austin chalk in the Travis County 

section; a few shells that appear to be indistinguishable from G. aucella have been found in the lower part 

of the Austin chalk, particularly in Gra,yson County. 

Two localities in a sandy facies of the Bonham marl 

in northeastern Texas have yielded specimens of 

Gryphaea wratheri. 

In Alabama shells that seem to be indistinguishable 

from Gryphaea wra:theri are present in considerable 

numbers in the upper part of the Tombigbee sand 

member of the Eutaw formation, where they are associated in places with Ostrea jolvnsoni and elsewhere 

with 0. cretaoea. Morton. Apparently, however, the 

Alabama occurrences are not exactly synchronous with 

the GryphaJea wratheri zone in Texas, for other considerations seem to indicate that the Tombigbee sand 

corresponds in age to a spmewhat higher zone in the 

upper part of the Austin; however, the exact age relation of the G. wra1theri zone in Texas to the Tombigbee 

sand has not yet been certainly determined. 

The shells of Ostrea johnsoni are present in great 

numbers in the upper 15 feet or less of the Tombigbee 

sand member of the Eutaw formation between Selma, 

Dallas County, and Montgomery, Montgomery County, 

Ala., where they are associated in places with Gryphaea 

wratheri. The species has not been found outside of 

Alabama.. Another much smaller species of oyster, 

0. cretacea Morton, occurs in great numbers farther 

west, in Perry, Hale, and Greene Counties, in the 

upper 15 or 20 feet of the Tombigbee sand, and also 

farther east, in Macon and Russell Counties, in glauconitic sand of the upper Tombigbee, but for some 

unexplained reason the two species, 0. cretacea and 

0. johnsoni, have not been seen together at any locality. 

Ostrea travisana occurs typically in Travis County, 

Tex., in the upper part of the Austin chalk within 

10 or 15 feet of the base of the overlying Taylor marl. 

Outside of Travis County it has been found near the 

1 
2 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 19 3 6 

top of the Austin at several localities between Bell 

County and Maverick County, and it occurs in Lamar 

County, in northeastern Texas, in a phosphatic bed 

at the base of the Brownstown marl immediately above 

the Blossom sand; it is worthy of especial note that this 

phosphatic bed lies some 200 feet or more below the 

Gober tongue of the Austin chalk, which, though 

continuous with the main body of the Austin, rises 

higher in the section than the uppermost part of the 

typical Austin section in Travis County. 

The species Ostrea elegantula White was originally 

described from the breaks of the "Red or Canadian 

River" in northeastern New Mexico. The species is 

present in 10 collections in the National Museum from 

localities of either uppermost Colorado or lowermost 

Montana age in northeastern New Mexico (pp. 7-8), 

6 of which were obtained by W. T. Lee and 4 by 

N. H. Darton ; three of then1 (coils. 6778, 7172, 7194) 

are recorded by Lee. 1 The species has also been collected by T. W. Stanton 2 near San Carlos, Presidio 

County, Tex., from beds believed to be of about the 

same age as those which yielded the species in New 

Mexico; at this locality the oyster was associated with 

M ortonioeras cf. M. delawarense (Morton). 

Five localities in the upper part of the Blossom 

sand in Red River County, Tex., distributed along a 

distance of 19 miles, have yielded Ostrea elegarntwla. 

The containing bed lies within 10 or 15 feet below the 

base of the overlying Brownstown marl. 

In Alabama the species has been found in an excellent state of preservation in marine glauconitic sand at 

two localities near Hatchechubbee, in Russell County. 

This sand, though similar lithologically to the Tombigbee sand member of the Eutaw formatipn, is estimated 

to be at least 100 feet stratigraphically higher and is 

a sandy facies representing the eastward extension of 

the basal part of the Selma chalk; in the vicinity of 

Hatchechubbee the sand is closely and conformably 

overlain by calcareous sandy clay of Selma age. 

In the absence of other evidence to the contrary the 

occurrences of Ostrea elegantula recorded in this paper 

may be interpreted as indicating the approximate age 

equivalence of the containing beds in Alabama, northeastern Texas, western Texas, and New Mexico. 

Each of the four species of Ostreidae treated in 

this paper is rather narrowly restricted in stratigraphic range and ,of more or less extended geographic range and is therefore of value as a zonal or 

index fossil. Ostrea elegmntula, which has the greates~ 

known geographic range of the four, appears to have 

come suddenly into the Gulf and New Mexican regions from some as yet undetermined previous habitat 

and to have survived for only a short time; however, 

1 Lee, W. T., U. S. Geol. Survey Prof. Paper 101, pp. 177, 193, 202, 

1917 [1918]. 2 Stanton, T. W., U. S. Geol. Survey Bull. 164, pp. 80, 81, 1900. 

its relationship to Ostrea ano1nioides Meek suggests 

that it may have had its evolutionary development in 

the early Upper Cretaceous seas of the Western Interior. Ostrea tr(Jfl)isarna, which appeared in the western Gulf region as a fully developed, conspicuously 

sculptured form and held its place there for only a 

brief period, may have had its origin in a European 

Upper Cretaceous sea where several analogous species 

lived at about the same time. Ostrea johnsoni, whose 

geographic range is the least of the four, came into 

the eastern Gulf region from an unknown source and, 

like the others, was able to hold its own for a short 

time only; however, this species is related to two larger 

species, 0. subsp(J)twl(J)ta Forbes and 0. owenarna Shumard, which are found in later Upper Cretaceous 

formations. 

Gryphaea wratheri may have had its evolutionary 

development within the Gulf region, for it is closely 

related to and may be a variant of G. au:cella Roemer. 

G. auoella ranges throughout the full thickness of the 

Austin chalk but is most nmnerous in the upper part 

of the chalk above the G. wratheri zone. 

Of the collections enumerated 40 were made by the 

writer, either alone or in company with others. Other 

persons who participated in making the collections, 

either alone or with others, include T. W. Stanton, 

C. A. White, R. T. Hill, T. W. Vaughan, N.H. Darton, 

W. T. Lee, C. W. Cooke, L. C. Johnson, A. C. McLaughlin, D. H. Walker, Jack Turrentine, J. K. 

Prather, W. P. Popenoe, and A. C. Munyan. 

The oysters were photographed in part by Harry S. 

Ladd, at the United States National Museum, and in 

part by N. W. Shupe, of the United States Geological Survey. The prints were retouched by Frances 

Wieser, of the Geological Survey. 

Gryphaea wratheri Stephenson, n. sp. 

Plate 1, figures 1-4 

Shell small for the genus, subcircular to broadly 

subovate in outline, inequilateral, strongly inequivalve. 

Left valve moderately and broadly convex, steepest 

on the anterior slope, most gently inclined toward the 

rear; the left valve of the holotype exhibits a shallow 

radial depression extending from just back of the 

beak obliquely downward and backward to the posteroventral margin; this feature is exceedingly variable in 

strength on different individuals and is entirely wanting on many of them. Beak of left valve weakly to 

moderately prominent, strongly incurved, direct, situated well in advance of the midlength; scar of attachment generally small but ranging on different individuals up to an observed maximum of 37 millimeters 

(rare), the larger scars markedly modifying the form 

of the shell. 
NEW UPPER CRETACEOUS psTREIDAE FROM THE GULF REGION 3 

Right valve flattish to broadly concave; beak small, wright, in Grayson County, a distance of 450 miles. A 

flattish, and inconspicuous. few feet above the top of the Gryphaea ttoTatheri zone 

Area small, triangular, much longer than high; re- is a layer ~f chalk containing the shells of Gryphaea 

silifer relatively large, more strongly impressed on the a1J)oe7la Ro mer in great numbers; this relation has 

left than on the right valve. Adductor scar of m.edium been obser ed along Little Walnut Creek in the vicinsize, subcircular to subovate in outline, moderately ity of Aus in, Travis County; on a branch of Deer 

impressed, situated about midway of the height, a Creek, 2m les southeast of Eddy, in Bell County; and 

little back of the midlength. The band of junction in the dra nage basin of White Rock Creek, in the 

of the two valves on the inner surface ranges in width northeaste outskirts of Dallas, Dallas County. The 

on average-sized shells from a minimum of 2 milli- species has been collected at two localities in a glaumeters adjacent to the upper anterior margin, to a conitic, sa dy layer in the Bonham marl (of upper 

maximum of about 13 millimeters within the rear mar- Austin age in Fannin County. 

gin; roughened areas are present on both the anterior Shells of this species are abundant in the upper 15 

and posterior dorsal ends of this band on each valve. A or 20 feet o the Tombigbee sand member of the Eutaw 

small slightly impressed pedal scar iS' present 2 to 4 formation n Alabama. The uppermost layer of the 

Inillimeters below the inner end of the resilifer. Tombigbee sand, as it has usually been defined, in the 

Surface of left valve marked with fine growth lines area betwe n Eutaw and Montgomery, consists of 4 

and with widely spaced nonprominent growth lamellae, to 8 feet o strongly calcareous, glauconitic sand conwhich become coarser toward the ventral margin. taining sc ttered but rather abundant phosphatic 

Surface of right valve ornamented on its lower half nodules an phosphatic internal molds of mollusks. 

by coarse upturned growth lamellae, which converge This layer ay mark a time of decrease in the amount 

and pinch out as they pass upward at both the front of clastic aterial deposited in a shallow sea, or it 

and the rear; the surface is further marked by a few may even 1 dicate emergence and erosion along a part 

fine, weak, widely spaced radial lines, such as char- of the belt ·f outcrop; however, farther west, at Plymacterize some other species of this genus in differing outh Bluff, on the Tombigbee River, 4 miles: west of 

degrees of strength. Columbus, iss., where the Tombigbee-Selma contact 

Dimensions of the holotype: Length 36.2 millime- is clearly e posed, phosphatic material is wanting, and 

ters, height 36 millimeters, thicknesS' measured from there appe rs to be a gradual transition from sand to 

the bottom. of the concavity of the right valve through chalk; it se ms unlikely, therefore, that the phosphatic 

the most convex part of the left valve 12 millime- bed in Ala ama indicates more than a diastem or, at 

ters. An occasional shell reaches a length of 48 or 50 the most, a erosion interval of short duration. If a 

millimeters. true uncon ormity is present at the contact the phosAmong the Upper Cretaceous Gryphaeas, this species phatic bed hould more logically be classed as the basal 

is most nearly related to Gryphaea a:ucella Roem.er, bed of the elma. chalk. 'Vhatever the interpretation, 

but it differs in its larger average size, its broader and Gryphaea ratheri, Ostrea cretacea Morton, and perproportionately more depressed form, and its some- haps other species are found both in the phosphatic 

what rougher surface. layer and i 10 or 15 feet of the undoubted TombigIn the vicinity of Austin, Travis County, Tex., the bee sand be ow this layer. G. wrather'i has been idenspecies is present in a restricted zone well above the tified from he localities enumerated below. 

middle of the Austin chalk as there developed. This Types: olotype, U. S. N. M. 75506; 2 figured 

zone has been traced northward to the vicinity of paratypes, T. S. N. M. 75507, 75507a; 36 unfigured 

White Rock Lake, in Dallas County, a distance of 180 paratypes 22 left and 14 right valves), U. S. N. M. 

miles. The maximum observed vertical range of the 75508. Na eel in honor of William E. '\~!rather, of 

species along this zone ( Gryphaea wratheri zone) is Dallas, Te · 

in a section along U. S. Highway 77, a mile northeast Distributio in Te:ras.-Upper middle part of Austin chalk 

of Sterrett, Ellis County; here the species ranges (Santonian) : Cut in Gaston Avenue ( U. S. Highway 67), just 

throughout 35 :feet of interbedded hard chalk and northeast of the intersection of West Shore Drive, 0.7 mile 

west of the dam of White Rock Reservoir, Dallas County softer marly chalk exposed in a gully 23 feet deep (14075,2a typ locality) ; hill south of the Orphans' Home 

just west of the highway and in a cut 12 feet high on road, 0.45 mi e west of White Rock Creek, at eastern edge of 

the east side of the highway. As seen in an exposure Dallas (1414 ) ; bottom of deep gully 23 feet below level of 

on South Cow Bayou, about 2% miles east of Bruce- U. S. Highw y 77, 1 mile northeast of Sterrett, Ellis County 

ville, McLennan County, the base of this zone lies in (17152) ; sou h of Red Oak Creek, southern part of Dallas 

quadrangle, ear Sterrett (3655) ; "blue rock" at a depth of the upper part of the zone of Inoceramus undulatoplic(J)tus, a narrow zone traceable in the Austin chalk 

from the Rio Grande in Maverick County to '\Vhite2a Numbers i parentheses under the heading "Distribution". here 

and on the fol owing pages are the collection numbers of 'the United 

States Geologic 1 Survey, unless otherwise indi"cated. 
4 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 1936 

34 feet, in a dug well near Sterrett (3656) ; on small branch 

paralleling the Missouri-Kansas-Texas Railroad at southwest 

edge of Waco, McLennan County (7561) ; northward-facing 

slope of Castleman Creek Valley, in gully north of northeastsouthwest road, 20 feet below road level, 2.6 miles southsoutheast of Hewitt, McLennan County (17151) ; Bullhide 

Creek about 10 miles southwest of Waco, McLennan County 

(2908) ; Bullhide Creek 0.6 mile below a northeast-southwest 

road 2112 miles northe·ast of Lorena, McLennan County (13808) ; 

South Cow Bayou, left bank, about 0.85 mile below the crossing of a northeast-southwest road, about 214 miles east of 

Bruceville, McLennan County (17150) ; ditch in northeastsouthwest road about 1 ~ miles northeast of Bruceville; McLennan County (17121) ; shallow quarry east of Fiskville 

road llh miles south of Fiskville, Travis County (7592) ; Walnut Creek below the Dessau road crossing, Travis County 

(7581) ; Williamson Creek between the upper and lower Lockhart road crossings, Travis County (Hill collection no. 51) ; 

left bank of Cibolo Creek about 1 mile above Schertz, Guadalupe County (7653). 

Sandy bed in Bonham marl (Austin age) : Road to Prospect 

Church, in bed of branch half a mile south of the church, 3 

miles north by west of Dodd City, Fannin County (9695) ; 

north of Lone Elm church and school, 3% miles northeast of 

Lannius, Fannin· County (9699). 

Distribution ~ A~ab ama.-Vpper part of Tombigbee sand: 

2 miles southeast of Eutaw (595) and in railroad cut a quarter 

of a mile east of Eutaw station (500), Greene County; Choctaw Bluff, Warrior River, Greene County (273, 6425) ; Erie 

Bluff, Warrior River (6428B) ; sec. 15, T. 18 N., R. 8 E·., near 

Hamburg, Perry County (321) ; public road a quarter of a mile 

south of o!d Hamburg ( 6441) ; Bluegut Creek near Selma, 

Dallas County (141); SE~ sec. 18, T. 17 N., R. 12 E .. , about 

7 miles east-northeast of Selma (142) ; Kenan's mill, about 3 

miles northwest of Selma (147, 149, 6829) ; Batte Smith Bluff, 

Alabama River, Sth miles. (air line) east of Selma (302, 6830, 

6831); Cunninghams Bluff, Alabama River, about 10 miles (air 

line) east of Selma (293) ; House Bluff, Alabama River, 15 

miles west-southwest of Prattville, Autauga County (296, 

6442B); Hall's field, sec. 24, T. 17 N., R. 13 E., Autauga County 

(300) ; field just east of cut of Louis-ville & Nashville Railroad 

2 miles southwest of Union Station, Montgomery (6832). 

Ostrea travisana Stephenson, n. sp. 

Plate 2, figure 5; plate 3, figures 1-5 

1884. ·Ostrea dilu.viana Linnaeus. White, U. S. Geol. Survey 

4th Ann. Rept., p. 295, pl. 40, fig. 1; pl. 41, figs. 1, 2. 

1893. Ostrea lliluviana Linnaeus. Cragin, T·exas Geol. Survey 

4th Ann. Rept. (Invertebrate paleontology, Cretaceous), 

p. 203. 

1898. Ostrea (Alectryonia) di'luviana Linnaeus. Hill and 

Vaughan, U. S. Geol. Survey 18th Ann. Rept., pt. 2, 

pl. 62, fig. 1. 

1901. Ostrea (Alectryonia) diluviana Linnaeus. Hill, U. S. 

Geol. Survey 21st Ann. Rept., pt. 7, pl. 45, fig. 2. 

1902. Ostrea (Alectryonia) diluviana Linnaeus. Hill and 

Vaughan, U. S. Geol. Survey Geol. ·Atlas, Austin folio 

(no. 76), ill us. sheet, fig. 42. 

1924. Ostrea sp. aff. 0. dilttviana Lirmaeus. Deussen, U. S. 

Geol. Survey Prof. Paper 126, pl. 10, fig. 1. 

1928. Alectryonia sp. aff. A. diluviana Linnaeus.. Adkins, Texas 

Univ. Bull. 2836, p. 104. 

All the illustrations given in the papers cited above 

pertain to the same shell (U. S. N. M. 8300), which 

is recorded as having come from Bell County, Tex. 

The species appears to belong to the subgeneric 

group to which Fischer von Waldheim 3 gave the name 

Aleotryonia, but I have not been able to · consult the 

original description. Presumably the principal distinguishing characteristic of the group is the strongly 

costate sculpture and the series of geometrically Vshaped projections and notches on the margin of each 

valve, the one series of which fits reciprocally into 

that of the other when the two valves are closed (see 

pl. 3, fig. 5). 

Shell large, thick, and exceedingly variable in outline, 

form, and coarseneSs of ornamentation; in some of the 

senile specimens in the collections the shell has grown 

thick and massive. The holotype, a right valve, is 

shorter in the length dimension than shells of average 

outline but is chosen .because of its completeness and 

its known stratigraphic position near the top of the 

Austin chalk. The paratype shown in plate 2, figure 5, 

which was found closely associated with the holotype, 

is a. much longer and a more coarsely ornamented 

right valve. · The large, incomplete paratype shown 

in plate 3, figures 3-5, which was. collected by Robert 

T. Hill and his associates, in 1894, would· have served 

better as a holotype, except that its stratigraphic position is not so exactly known ·; it was found near an 

igneous dike cutting the Selma chalk, and its position 

is believed to be approximately the same as that of the 

holotype. 

Typical shells curve noticeably toward the rear. 

Both valves exhibit a · more or less. prominent and 

sharply developed umbonal ridge, which lies near or 

in advance of the midlength and which may or may 

not flatten out toward the postero-,ventral margin. 

The two valves are rather strongly and nearly equally · 

inflated, though the left valve may be a little plumper 

than the right; the anterior slope is generally much 

steeper than the posterior one. The scar of attachment 

on the left valve varies greatly in size and is very large 

on some shells. On most shells there is a postero-dorsal 

winglike extension, but this is an exceedingly variable 

feature on different individuals. The beak is not very 

prominent on either valve and is generally situated 

anterior to the midlength of the hinge line. 

On the holotype the hinge line at the base of the 

area, is 33 millimeters long. The area is roughly triangular, with its longest dimension on the base, and 

is 11 millimeters broad at right angles to the hinge 

line below the beak; the· resilifer is triangular, relatively broad, and most deeply impressed on the left 

valve. Adductor scar large, deeply impressed, elongated in the direction of the height, narrowest above, 

with upraised margins, situated close to the posterior 

s Fischer .von Waldheim, Gotthelf, Museum-Demidoff (mis en ordre 

sysN:;matique et descrit par G. Fischer), ou Catalogue ... des curiosites 

de la nature et de l'art, donnees a l'Unlversite imperiale de Moscou, 

par. P. de Demidoff, tome 3 (in 1 vol.), illustrated, 1807. 
NEW UPPER CRETACEOUS OSTREIDAE FRO THE GULF REGION 5 

margin and very high in the shell. Pedal scar tiny, 

situated a few millimeters below the inner, anterior 

edge of the resilifer. The margins of the shell present 

a series of deeply indented, geometrically V -shaped 

notches, those of the two valves fitting reciprocally 

into each other (pl. 3, fig. 5). 

The surface of each valve is strongly and similarly 

ornamented with prominent, narrow costae that are 

V -shaped in cross section; away from the beak costae 

are added by bifurcation and intercalation, mainly, 

though not exclusively, along the umbonal ridge; the 

costae tend to become irregularly noded along their 

crests. The ribbing varies greatly in coarseness on 

different individuals from the same and from different 

localities, the number of ribs ranging from 20 to 35. 

The ornamentation on the right valve of the specimen 

shown in plate 3, figure 3, indicates a pathologic condition, perhaps due to an injury; apparently the part of 

the mantle that gives rise to the shell along the line 

of the umbonal ridge was shoved forward, thus initiating a new stage of growth back of the ridge. 

Dimensions of the holotype as oriented with the 

hinge line in the horizontal position : Length 84 millimeters, height 102 millimeters, convexity 31 millimeters. Dimensions of the incomplete paratype (pl. 2, 

fig. 5) from the locality of the holotype: Length 110 

millimeters, height 105+ millimeters, convexity 26 

millimeters. Dimensions of the large incomplete paratype from Onion Creek, Travis County, Tex. (pl. 3, 

figs. 3-5) : Length 90 + millimeters, height 120 + millimeters, thickness 66 millimeters. These measurements 

emphasize the great variability in outline and form 

of the individuals of the species. 

This species has been found at several widely separated localities in the upper part of the Austin chalk, 

from Maverick County to Bell County, Tex. The bolotype and one paratype were collected on Little Walnut 

Creek in Travis County within 10 feet of the top of 

the Austin. In northeastern Texas the species was 

found, originally by T. W. Stanton, near Paris, Lamar 

County, in glauconitic sandy marl forming the base 

of the Brownstown marl of that area, immediately 

above the Blossom sand; several collections have subsequently been made at this locality. The containing 

bed is believed to correspond approximately in age 

to that which yielded the species on Little Walnut 

Creek, Travis County. 

As indicated in the synonymy, several American authors have referred this species to Ostrea dilu.viana 

Linnaeus,4 which was originally described from the 

Upper Chalk of Sweden. Linnaeus' species, as later 

figured by Nilsson,5 though similarly ornamented, is 

4 Linne, Caro1i a, Systema naturae, ed. 12, tome 1, pars· 2, p. 1148, 

1766. 5 Nilsson, -s., Petrificata suecana, pars prior, p. 32, pl. 6, figs. lA- B, 

fig. 2, 1827. 

er and more strongly curved than 0. travisana, the mbonal ridge is sharper and more slender, 

and the t o are believed to be distinct. The figures 

given by isinger 6 indicate a broadly ovate shell more 

like 0. t omuaruJ), but the adductor · scar is proportionately arger and more broadly ovate, and is not 

quite so ear the posterior margin. 

Alectry nia deshayesi Fischer,7 from the Santonian 

of the Cr' ean Peninsula, south Russia, appears to be 

a close a alog of 0. travisana. As figured by H. 

Coquand, Ostrea deshayesi has a larger and broader 

adductor car which is not quite so high on the inner 

surface, a d a more elongated resilifer. 

Ostrea santonensis D'Orbigny,9 from the lower 

Senonian of France, appears also to be closely analogous to 0 travisana. 

It is wo thy of note that both 0. deshayesi, from the 

Santonia , and 0. santonensis, from the lower 

Senonian, occupy about the same stratigraphic position in E rope as does 0. travisana in America. 

Types: Holotype, U. S. N. M. 75·509; 1 figu'red 

para type, U. S. N. M. 75510; 1 figured para type, 

U. S. N. . 75511. 

Distribut on in Tewas.-Upper part of Austin chalk (upper 

Santonian) Bell County (U. S. N. M. 8300, figured as indicated in th synonymy) ; old Sprinkle road (abandoned) on 

westward-£ cing slope of Little Walnut Creek Valley near 

iron bridge 2 miles southwest of Sprinkle, Travis County 

(14159, loc lity of holotype and one paratype) ; Ca:meron 

road, east ard-facing slope of Walnut Creek valley, threefifths mile west of Sprinkle, Travis County (14068) ; near 

Austin, Tr vis County (Hill collection no. 7) ; Onion Creek, 

half a mil below the lower Lockhart road crossing near a 

big dike·, ravis County (Hill collection no. 43, locality of 

one paratyp ) ; Cibolo River 1;4, miles above Galveston, Harrisburg & Sa Antonio Railway bridge at Schertz, Guadalupe 

County (76 4); Tequesquite Creek a few hundred yards below 

the crossin of the Eagle Pass-Del Rio road, Maverick Gounty 

(8229, 1085 ) . 

Basal ph sphatic sandy bed of Brownstown marl: On a 

small creek quarter to half a mile south of the crossing of the 

Texas & P cific Railway and the Texas Midland Railroad, 

at the sout west border of Paris, Lamar County (7508, ,13078, 

17148). 

Ostrea johnsoni Stephenson, n. sp. 

P ate 1, figures 11, 12; plate 2, figures 1-4 

medium size, thick in the umbonal region, 

becoming thin and frail at the ventral margin, subovate in utline, elongated in the direction of the 

height, su equilateral, slightly inequivalve. Left valve 

slightly m re convex than the right one. On the right 

valve a b oad ridge or fold originates at or below 

e Risinger, ., Litbaea svecica seu Petrificata sveciae, p. 49, tab. 14, 

figs. 5a, b, 18 7. 

7 Fischer, . (de Waldbeim), Bull. nat. Moscou, tome 8, pl. 2, 1834. 

s Coquand, ., Monogra-pbie du genre Ostrea, terrain cretace, p. 88, 

pl. 23, fig. 1, 869. 

9 D'Orbigny A., Paleontologie" francaise, Terrain cretace, Lamellibrancbes, p. 7 6, pl. 484, figs. 1-3, 1846. 
6 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 19315 

the midheight and extends with increasing breadth 

to the ventral margin; opposed to this ridge on the 

left valve is a broad depression. Beak of left valve of 

medium prominence, dull-pointed, weakly incurved, 

roughened on the tip by a small scar of attachment, 

situated centrally; beak of right valve small, nonprominent, overtopped by the beak of the left valve. 

Dorsal margin of left valve broadly arched; that of 

right valve nearly straight. The anterior and posterior 

margins of the shell diverge somewhat from the ends 

of the hinge and pass below into the rather sharply 

rounded ventral margin, the trend of which in some 

adults is sinuous as a result of the broad reciprocal 

fluting of the two valves. In larger, typical adult 

shells the margins of the two valves are reciprocally 

and broadly sinuous all the way around below the ends 

of the hinge, the sinuosities including nine bends, five 

convex to the right and four to the left as the shP.ll 

is held with the beaks upward and the front edge 

away from the observer ; in most shells of less than 

three-fourths adult size the sinuosities of the margins 

are seen only in their incipient stages; however, an 

occasional haH-grown shell has these curves conspicuously developed; on the other hand, the margins of 

many adults are straight or only weakly sinuous. 

Hinge line of holotype about 25 millimeters long; 

area of left valve 10 millimeters high above hinge line, 

that of right valvH 8 millimeters high. Resilifer broad, 

deep on the left valve, shallow on the right. Area 

finely striated with growth lines. Adductor scar large, 

elongate-ovate, the elongation directed obliquely upward toward the rear, situated posteriorly below the 

midheight; The pedal scar appears as a small pit 

on the inner surface, 2 to 5 millimeters below the inner 

edge of the resilifer. 

In addition to the sharply developed growth lines 

the surface of each valve presents a series of gentle, 

concentric undulations, the crests of which are 5 to 

10 millimeters apart in the vicinity of the midheight; 

these tend to smooth out toward the margins ; an 

occasional specimen exhibits fine radial lining in the 

umbonal region. 

Dimensions of the holotype: Length 54 millimeters; 

height 75 millimeters; thickness 31.5 millimeters; the 

largest specimen measured is 83 millimeters high. 

In outline, in surface features, and in the shape 

and low position of the adductor scar this species resembles Ostrea subspatulata Forbes, which occurs ·in 

the Peedee formation of North Carolina and in the 

upper part of the Ripley formation in eastern Alabama and adjacent parts of Georgia; however, 0. 

jol&fuwni averages scarcely half has large as 0. subspatulata; lacks a strong bend to the left in the ventralportion, has a sinuous margin in the typical adult, 

and is· more finely )sculptured. 

The shells of this species are abundant in the upper 

15 feet or less of the Tombigbee sand member of the 

Eutaw formation and have been collected at 9 localities in this zone from the vicinity of Selma, Dallas 

County, to the vicinity of Montgomery, Montgomery 

County, Ala., an air-line distance of 40 miles. Fossils 

associated with the species include the echinoid genus 

H ardourinia.~ and the mollusks Gryphaea wratheri 

Stephenson, Ewogyra Uipatoiensis Stephenson, Baoulites 

as per Morton, and Placenticeras aff. P. guadalupae 

(Roemer). 

Types: Holotype, U.S.N. M. 75512; 1 figured paratype, U. S. N. M. 75513; 2 figured paratypes, 

U. S. N. M. 75514, 75514a; 15 unfigured paratypes, 

U. S. N. M. 75515. Named in honor of the late L. C. 

Johnson, a pioneer student of Cretaceous and Tertiary 

geology in Alabama. 

Distribution in Alabama.-Upper part of Tombigbee sand 

member of Eutaw sand in Alabama: Ravine half a mile west 

of Kenan's mill, 3 or 3¥2 miles northwest of Selma, Dallas 

County (6828) ; bluff on Valley Creek 100 yards above the 

crossing of U. S:. Highway 80, northwest of Selma (16997) ; 

SE~ sec. 18, T. 17 N., R. 12 E., about 7 miles east-northeast of 

Selma (142) ; Bluegut Creek near Selma (141) ; Batte Smith 

Bluff, Alabama River, Dallas County (302; 6830, locality of bolotype, 1 figured paratype, and 15 unfigured paratypes; 17044); 

at and in fields near House Bluff, Alabama River, Autauga 

County (296, 6442B; 17011, locality of 2 figured paratypes) ; 

Woods Bluff, Alabama River (304); Cunninghams Bluff, 

Alabama River (293); Coatoma Creek, 0.9 mile northeast of 

Mount Moriah Church, in NW~ sec. 32, T. 16 N., R. 17 E., 

Montgome·ry County (17010, lower 5 feet of section; 17009, 

upper 3 feet of section). 

Ostrea elegantula White 

Plate 1, figures 5-10 

1876. Ostrea elegantula Newberry, Geological report, in Macomb, 

J. N., Report of the exploring expedition from Santa 

Fe, N. MEx., to the junction of the Grand and Green 

Rivers, p. 33. (Named without description or illustration, and therefore at this stage a nomen nudum.) 

1884. Ostrea elegantula Newberry. White, U. S. Geol. Survey 

4th Ann. Rept., p. 295, pl. 36, figs. 5-7. (Authorship 

ascribed to Newberry, who, however, bas neither a 

published nor a manuscript claim to authorship.) 

1903. Ostrea anom1oides var. narnus Johnson, School of Mines 

Quart., vol. 24, p. 185, pl. 1, figs. lOa-d, 1903. 

1908. Ostrea anomioides var. nanus Johnson. Shimer and 

Blodgett, Am. Jour. Sci., 4th ser., vol. 25, p. 61, 1908. 

The following description is based mainly on shells 

from Alabama which a.re well preserved, in contrast to 

the poor state of preservation of the types and also of 

most of the other material from the type region in 

New Mexico. 

Shell small, thin, often translucent in transmitted 

light, broadly subova.te to· subquadrate in outline, 

squarish above, inequilateral, strongly inequivalve. 

Left valve of medium convexity, greatest inflation below the beak, a.hove the midheight; anterior slope 
NEW UPPER CRETACEOUS OSTREIDAE FROM THE GULF REGION 

steep above, becoming slightly less steep toward the 

margin; upper posterior slope more gentle, flattening 

and broadening toward the margin to form a slight 

winglike extension. Right valve nearly flat. Beak of 

left valve slightly prominent, incurved, direct, situated 

about two-fifths the length of the shell from the anterior extremity; beak of right valve small, flat, nonprominent. 

Area very small, triangular, longest on its inner margin; resilifer relatively broad, shallow, most strongly 

impressed on left valve. Adductor scar small, ovate, 

situated back of the midlength at about the midheight. 

The pedal scar appears on each valve as a small pit high 

on the inner surface about 2 millimeters below the 

inner end of the resilifer. Both the inner antero- and 

postero-dorsal margins are faintly crenulated for short 

distances away from the ends of the hinge line. 

Surface of left valve ornamented with a series of 

delicate, slightly upraised, elegantly crinkled concentric 

lamellae, spaced 1 to 2 millimeters apart; the crinkles 

on different lamellae are alined radially and represent 

weak radial costae. Surface of right valve covered with 

gentle, narrow, concentric undulations on which very 

faint crinkling may be detected. 

Dimensions of the left valve shown in plate 1, figures 5-7: Length 17.5 millimeters, height 21 millimeters, convexity 5 millimeters. This specimen is about 

maximum size for the Alabama shells, but some of the 

Texas shells are as much as 25 millimeters high, and 

the two cotypes, right and left valves, are respectively 

31.2 and 26 millimeters high; among the New Mexico 

collections an occasional shell may reach as much as 

40 millimeters in height. 

In the well-preserved Alabama material the individual shells exhibit considerable variation in form . ' outhne, and strength and coarseness of ornamentation. When these differences are taken into consideration it does not seem practicable to separate the Alabama and Texas shells from White's species from New 

Mexico. 

The two co types are recorded as having come from a 

section on the "Red or Canadian River" in northeastern New Mexico. One is a left valve with the outer 

shell layers partly scaled off but retaining faint impressions of the characteristic fine, crinkled ornamentation like that so well preserved on the Alabama 

shells; the other is a right valve which, except for its 

larger size, is like the right valves from Alabama. 

The concentric growth lines on the left valve seem to 

indicate that the posterior wing is weakly developed 

on this cotype, but this wing is present in typical form 

on other shells from the type region in northeastern 

New Mexico; these specimens were identified by T . W. 

Stanton. Although Newberry recorded this species as 

associated with other species of mollusks of upper 

65752-36--2 

Benton age, T. W. Stanton and J. B. Reeside 10 state 

that all the later collections came from beds that lie 

stratigrapHically near the boundary between the Colorado and Montana groups; they believe that the 

original record is in error. 

Ostrea gantula is present in 10 collections in the 

National ~useum from localities in northeastern New 

Mexico, 6 of which were obtained by W. T. Lee and 4 

by N. H. Darton; 3 of them (collections 6778, 7172, 

7194) are !recorded by LeeY The species has also 

been colleded by T. W. Stanton 1 2 near San Car los, 

Presidio County, Tex., from beds believed to be of 

about the same age as those which yielded the species 

. N M 1· Ill ew eiXICO. 

Ostrea arwmioides Meek,13 which was originally described from the Missouri River below Gallatin, Mont., 

is obviously closely related to 0. elegantu1la, but the 

type mate~ al in the National Museum indicates a 

stronger development of narrow, concentric ribs, or 

folds, and a very weak development of the fine crinkling of the concentric lamellae. Inasmuch as present 

available ef idence suggests that Meek's species came 

from beds Gf lower Colorado age,1 4 and in view of the 

differences in ornamentation just noted, it seems reasonable to !regard 0. anomioides as distinct from 0. 

elegantuZa. 

In Texas the species has been collected from 5 

localities in the upper part of the Blossom sand in 

Red River County along a distance of 19 miles. 

Types: Two cotypes, U. S. N. M. 18611; from the 

breaks of the Canadian River, in northeastern New 

Mexico. or the back of one of the labels accompanying the ty~ s T. vV. Stanton has written: "It is questionable wlliether this really came from the Colorado 

group. Many specimens apparently referable to 

Ostrea eleg;lantula were collected by Lee in the Hagan 

coal field, ~ear lTna del Gato, New Mexico." The beds 

that yieldeCl the oyster in the Hagan coal field are 

included by Lee in the Mesaverde formation and are 

interpreted! to be of lower Montana age. One plesiotype from the base of the 1\1esa verde formation in the 

Hagan coal field is figured, U. S. N. M. 75517. Two 

plesiotypes from marine sand of lower Selma age 

near Hatchf chubbee, Russell County, Ala., are figured, 

U. S. N. M. 75516 and 75516a. 

Distr·ibution in New Niea:'ico.-Upper part of Mancos shale 

(transition IIJeds) : 2 miles southwest of Madrid (716'4) ; 

about a mile ! southwest of Waldo (7165) ; road from Cabezon 

to Raton Sp:rrings (7194) ; east flank of Ortiz Mountain, near 

Omara mine ( 7180). 

10 Oral communications. 11 Lee, W. T., U . S. Geol. Survey Prof. Paper 101, pp. 177, 193, 202, 

1917 [1918] 0 

12 Stanton, 'L'. W., U. S. Geol. Survey Bull. 164, pp. 80- 81, 1900. 

1a Meek, F. B., U. S. Geol. Survey Terr. 6th Ann. Rept., for 1872, 

p. 488, 1873. White, C. A. , U. S. Geol. Survey Terr. 12th Ann. Rept., 

for 1878, p. 10, pl. 11, figs. 4a, 4b, 1883. 14 Stanton, T J W., U. S. Geol. Survey lVIon. 32, pt. 2, p. 633, 1899. 
8 SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY, 19 3 6 

Basal part of Mesaverde formation: Garcia & Goebel mine, 

30 feet above coal seam, northwest of Socorro (9606) ; same 

locality 40 feet above coal seam (9607) ; Herring mine, 50 

feet above coal seam, 20 miles northeast ,of Socorro (9608) ; 40 

feet above coal seam, 11A miles south of Perry Cox place, 

15 miles north of Carthage ( 9764) ; Hagan coal field, from 

sandstone below the coal ( 6778, 1 specimen figured) ; Hagan 

coal field, 500 feet south of mine opening (7172). 

Occurrence in Presidio County, Tex.-Overturned beds 

near shaft of San Carlos coal mine, 21h miles southeast of 

store at San Carlos (1468). 

Distribtttion in Red River County, Tex.-Upper part of 

Blossom sand: Out in Reed's store road just south of Pecan 

Bayou, about 2 miles north of White Rock ( 1356,1, 16675) ; 

field west of road 0.4 mile south of Vandalia (13079, 17149) ; 

small earth tank east of Dimple road near foot of northwardfacing slope of branch of Tanyard Bayou, 4.2 miles- north by 

west of public square at Clarksville (17126) ; old Clarksville 

road 2.2 miles east-southeast of Detroit ( 17153) ; head of 

ravine east of old Clarksville road 1.4 miles southeast ·of 

Detroit ( 17125). 

Distribution in Alabama.-Marine sand of lower Selma age: 

Cut of Central of Georgia Railway half a mile east of Hatchechubbee, Russell C()unty (6825, locality ()f two figured specimens; 17005) ; east end of cut in State Highway 26, 5.1 miles 

west of Hatchechubbee (17003). 
PLATES 1-3 

9 
PLATE 1 

[Figured material is deposited in the United States National Museum] 

FIGURES 1-4. Gryphaea wratheri Stephenson, n. sp. 1, Exterior of left valve of holotype (U. S. N. M. 75506); 2, exterior of right 

valve of holotype; 3, interior of a paratype, a left valve (U. S. N. M. 75507); 4, interior of a paratype, a right 

valve (U. S. N. M. 75507a). 

5-10. Ostrea elegantula White. 5, Exterior of a left valve from cut of Central of Georgia Railway half a mile east of 

Hatchechubbee, Ala. (U. S. N. M. 75516); 6, enlargement of the same shell; 7, interior of the same shell; 8, 

exterior of a right valve from the same locality (U. S. N. M. 75516a); 9, interior of the same right valve; 10, 

exterior of an imperfect left valve from sandstone below the coal, in Hagan coal field, N. Mex. (U. S. N. M. 

75517). 

11-12. Ostrea johnsoni Stephenson, n. sp. 11, Exterior of a paratype, a left valve (U. S. N. M. 75514); 12, interior of a 

paratype, a left valve (U.S.N. M. 75513). 

10 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 1 

NEW UPPER CRETACEOUS OSTREIDAE FROM THE GULF REGION 
U.S. GEOLOGICAL SI;RVEY PROFESSIONAL PAPER 186 PLATE 2 

NEW UPPER CRETACEOUS OSTREIDAE FROM THE GULF_REGION. 
PLATE 2 

[Figured material is deposited in the United States National Museum] 

FIGURES 1- 4. Ostrea johnsoni Stephenson, n. sp. 1, Exterior of left valve of holotype (U. S. N. M. 75512); 2, exterior of right 

valve of holotype; 3, front edge view of holotype; 4, front edge view of a small paratype (U.S. N. M. 75514a). 

5. Ostrea travisana Stephenson, n. sp. Exterior of paratype, a right valve of more than average length (U. S. N. M. 

75510). 

11 
PLATE 3 

[Figured material is deposited in the United States National Museum. All figures slightly reduced) 

FIGURES 1-5. Ostrea travisana Stephenson, n. sp. 1, Exterior of holotype, a right valve (U. S. N. M. 75509); 2, interior of halotype; 3, exterior of right valve of a paratype from Onion Creek, Travis County, Tex. (U. S. N. M. 75511); 4, 

exterior of left valve of the same paratype and right valve of another individual to which the paratype is attached; 

5, front edge view of the same paratype. 

12 

0 
U. S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 186 PLATE 3 

NEW UPPER CRETACEOUS OSTREIDAE FROM THE GULF REGION.