68 
BULLETIN OF THE LABORATORIES 
been seen, but there is at least a close resemblance to Winchell’s spe- 
cies as gathered from the description. 
Shell small, compressed, elongate elliptical, with nearly parallel 
margins and sub-terminal beaks. Rather more than twice as long as 
high, height nearly the same anteriorly as posteriorly. Hinge-line 
two -thirds the entire length, often diverging posteriorly, sometimes 
shorter ; postero-dorsal margin very obliquely truncate, curving more 
rapidly near the middle of the height and passing by a rapid curve into 
the nearly straight ventral margin. Anterior margin rather distinctly 
concave above the middle, strongly convex bejow. Beaks minute, 
not projecting, near the front; posterior-umbonal slope gentle, no well- 
defined ridge; shell thin, surface marked by fine lines of growth. 
Length 13 mm, height 5.2 mm ; hinge-line 8 mm ; beak 2 mm. from 
anterior. Shale 4 feet below Congl. I, at the “ Dug- way,” Granville, 
Ohio. No. 1372. 
Sanguinolites [Splienotivs) f vans versus, Dekoninck. 
Sanguinolites (Cypricardia ?) rigida. W. and W. 
(Plate IX, Fig. 22. ) 
Shell elongate, quadrangular, a little widest at the posterior end. 
Dorsal line straight, bounded by a rather broad escutcheon, which 
is more than half as long as the entire length of the shell. Anterior 
end truncate, prolonged near the basal margin ; posterior extremity 
obliquely truncate; basal line straight, slightly emarginate, a little an- 
terior to the middle, by a shallow sinus which crosses the shell from 
beak to base. Lunule large, deeply marked; beaks small, flattened 
on the umbones, and enrolled, situated anteriorly ; umbonal ridge 
very prominent and angular, extending from the beak to the posterior- 
basal angle. A second, but less prominent ridge passes about mid- 
way between the first and dorsal line. Surface marked by sharp, 
closely-arranged lines, parallel to the margin, which are bent at right 
angles as they cross the umbonal ridge, and less abruptly at the minor 
ridge. Interior of shell with a sharp muscular ridge passing from the 
anterior side of the beaks, with a forward curvature, about yi distance 
across the shell. Hinge-teeth absent, probably partially external lig- 
ament,” 
