410 
PALAEONTOLOGY OP NEW-YORK. 
GENUS VITALINA (Hall). 
Y itulina : Hall, Thirteenth Report on the State Cabinet, p.72. 1860. 
Shell plano-convex : hinge-line extended : valves articulating by teeth 
and sockets. 
Ventral valve gibbous, with a high area, and large triangular fissure. A 
callosity or false area in the bottom of the fissure. Dental lamellaa 
thick and strong. 
Dorsal valve depressed-convex, with a scarcely perceptible area; a 
strong cardinal process, which is conspicuous at the base of the fissure 
in the closed valves. 
Surface plicated, papillose : shell-structure punctate. 
Vitalina pustulosa. 
PLATE LXII. 
Vitulina pustulosa : Hall in Thirteenth Report on the State Cabinet, p. 82. 1860. 
Shell subplano-convex, semielliptical : hinge-line equalling or a little 
less than the width of the shell : surface marked by a few strong pli¬ 
cations, and covered by minute papillae, which appear like the bases 
of setae. Substance of the shell finely punctate. 
Ventral valve very convex; the apex a little arcuate, subangular in the 
middle above, and the elevation continued in a broad fold which is at 
first flattened and then becomes grooved or duplicate below, with four 
or five rounded or subangular plications on each side; the arga much 
elevated, and the margin sloping rapidly from the apex to the cardinal 
extremities : foramen large and wide, being half the length of the 
area, and reaching to the apex; deltidial pieces or pseudo-deltidium 
unknown. 
Dorsal valve flat or slightly convex, with a wide mesial depression 
which is nearly flat in the bottom, and in larger specimens has a shal¬ 
low groove in the middle towards the front. The plications on the 
sides correspond with those of the ventral valve. There is a narrow 
scarcely perceptible area. 
