Casey — Notes on the Pleurotomidae. 143 
erable number by Mr. T. H. Aldrich, to whose generosity I 
owe ‘the examples before me. 
Cochlespiropsis nh. gen. 
This genus is allied to Cochlespira but differs greatly in 
having the beak obliquely elevated near the tip, the periphery 
of the whorls simply angulate in profile and not lamellarly 
expanded, reflexed or crenulate and the sculpture extremely 
minute and feeble, close-set and even, wholly differing in 
character from that prevailing in Cochlespira. The genus 
seems to have become extinct by the middle of the Eocene, 
not occurring above the Lower Claiborne, and, in fact, limited 
as far as known to that epoch. The two species before me 
may be distinguished as follows : — 
Spire above the periphery of:the body whorl evenly and rather rapidly 
acuminate, shorter than the portion below that periphery; sculpture of 
the body whorl below the periphery consisting of moderately close- 
set and distinct spiral threads which are somewhat uneven in size. 
Length of a specimen of 7 body whorls, 20 mm.; width, 6.5 mm. 
Lower Claiborne Eocene of Wheelock, Texas.......... engonata Con. 
Spire above the periphery more elongate, nearly equaling in length the 
portion below, very gradually acuminate and more rapidly and 
arcuately so toward apex; ornamentation of the body whorl below the 
periphery consisting of extremely minute, closely crowded and equal 
spiral threads which are frequently somewhat wavy or subinterrupted 
by uneven irregularities of growth. Length of a specimen of 8 body 
whorls, 31 mm.; width, 8.8mm. Lower Claiborne Eocene of Lisbon, 
TAU Sverc cteversicia  leverarartarauaicter et ciatarelietaencle aac ate helevaelelslersioné sisierslecel’ blanda n. sp. 
There is no vestige of a tumid or carinulate collar below 
the suture in this genus. 
Cochlespira Con. 
The periphery is lamelliform to a greater or less degree in 
this genus, the edge always crenulate and bent backward, and 
there is usually a well-marked and finely beaded collar below 
the suture which, however, sometimes becomes obsolete on 
the larger whorls. The posterior broad fasciolar surface has 
some fine spirals near the periphery but is usually completely 
devoid of sculpture elsewhere, except the arcuate lines of 
