450 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 127 
Highway 70, 14 miles northwest of Murfreesboro, Murfreesboro (15’) Quad- 
rangle. 
Genus DOLEROIDES Cooper, 1930 
Doleroides Coorer, Journ. Paleont., vol. 4, pp. 375, 382, 1930.—SCHUCHERT and Cooper, Mem. 
Peabody Mus. Nat. Hist., vol. 4, pt. 1, p. 63, 1932. 
DOLEROIDES COMPRESSUS Cooper, new species 
Plate 96, B, figures 22-38 
Small for the genus, wider than long, broadly elliptical in outline; hinge nar- 
rower than the midwidth; greatest width slightly anterior to the middle; sides 
nearly straight and slightly oblique outward; anterolateral extremities narrowly 
rounded ; anterior margin broadly rounded ; anterior commissure rectimarginate ; 
surface multicostellate; costellae unequal in size, numerously intercalated and 
usually fasciculate, 10 to 14 in 5 mm. at the front margin. 
Pedicle valve with greater depth than the brachial valve, moderately convex 
in lateral profile ; strongly convex in anterior profile with the median region nar- 
rowly rounded; umbonal region narrowly swollen; median region swollen with 
moderately steep and fairly long slopes to the margins. Interarea curved, apsa- 
cline; muscle impression fairly long and with fairly wide diductor scars; dental 
plates short; pallial impressions not preserved. 
Brachial valve gently convex in both profiles and with the greatest convexity 
in the median region. Sulcus originating on the umbo, short and shallow and 
confined to the posterior half; sulcus barely perceptible on the anterior half of 
the valve ; flanks gently inflated ; lateral slopes short and gentle. Cardinal process 
a thin septum; notothyrial chamber moderately deep; brachiophores short; sup- 
porting plates depressed. 
Measurements in mm.— 
Brachial Hinge 
Length length Width width Thickness 
EL OIG ty DE, on Paves Fons, Wn He 11.6 II.0 14.4 10.7 5.3 
Paratype (110607b) ......... 10.8 10.3 12.9 0.8 5.4 
a (rzo060sa)iie nus, 13.1 12.0 15.3 10.0 7.5 
Types——Holotype: 110607c; figured paratypes: 110596a, 110607a,d-f; un- 
figured paratypes: 110596b-h, 110605a, 110607b. 
Horizon and locality—Bromide formation (Mountain Lake member) in Okla- 
homa: On the east side of Oklahoma Highway 18, sec. 11, T. 1 S., R. 3 E., 1.8 
miles south of Sulphur, Murray County. 
Discussion.—This species is abundant in the road cut south of Sulphur but 
was not seen at the same horizon on Spring Creek. The complete specimens 
illustrated are adults, but they are young ones. The species evidently attains a 
size nearly double that of the figured specimens but retains its compressed form 
except for a few occasional obese specimens. The compressed form is the chief 
characteristic of the species and differentiates it from the similar D. oklahomensis. 
