602 TRANS. OF THE ACAD. OF SCIENCE. 
terior slope, and in the most perfect specimen before me 
there are six or seven quite prominent radiating lines on the 
buccal end of the shell. 
Length, 1.88 inches; height, 1.58; thickness, 1.40. 
Form. and Loc.—Comanche Peak, and Parker County» 
near the Brazos river. Near base of Upper Cretaceous in the 
Caprotina Limestone. : 
Dedicated to my friend, Hiram A. Prout, M.D., President 
of the Academy of Science of St. Louis. 
GENUS LUCINA. 
L, SUBLENTICULARIS, N. Sp. 
Shell rather large, subcireular, compressed convex ; length 
slightly greater than the width; anterior and pallial margins 
regularly rounded; anal margin gently convex, or oa y 
truncate ; posterior cardinal margin gently arched, and de- 
clining from the beaks posteriorly ; ligament area narrow /an- 
ceolate, deeply excavated and with sharply carinate pa 
beaks obtuse, small, very little elevated, directed anterlony, 
antemedial, not in contact; surface marked with numerous, 
fine, concentric, unequal lines of growth. 
Length, 1.87 inches; width, 1.74; thickness, 0.74 
Form. and Loc. — Bluffs of Red River, in Lamar = 
Fannin Counties, from Septaria embedded in the indura 
marl, near the base of the Lower Cretaceous Group, ore 
ted with Ammonites Swallovii, Inoceramus capulus, and Ge 
vilia gregaria. Collected by G. G. Shumard. 
GENUS NUCULA. 
N. HayYpENI, n. Sp. 
Shell subtriangular, ovate, somewhat gibbous in the oor 
nial region; width equal to three-fourths of the length 4 cad 
semioval; cardinal marg i 
gradually to posterior end; corselet depressed, re face or 
lanceolate, marked with oblique, transverse T1085 Me th nu- 
namented with fine waved lines of growth, crossl" ais, 
merous, fine, radiating strie, with finer lines in the} 
poe ND le 
