158 UNIVALVE SHELLS 



volutions five and a half, wrinkled across and 

 rounded; suture rather deeply impressed; aperture 

 wide, embracing a rather small portion of the penul- 

 timate whorl; labrum not reflected; umbilicus large, 

 distinctly exhibiting all the volutions to the apex. 



Greatest transverse diameter, nearly one inch and 

 one fifth. 



Inhabits Lower Missouri. 



But a single specimen was found ; it was a dead 

 shell, destitute of its epidermis. It is avery dis- 

 tinct species. 



13. H. ^jejuna. Shell subglobular, glabrous, 

 pale reddish-brown; volutions five, slightly wrin- 

 kled, regularly rounded; spire convex; suture rather 

 deeply impressed; aperture dilate-lunate; labrum 

 a little incrassated within, not reflected; umbilicus 

 open, small; 



Breadth rather more than 1-5 of an inch. 



Inhabits the Southern States. 



Animal — light reddish-brown, with a granular 

 surface, longer than the breadth of the shell ; oculi- 

 ferous tentacula elongated, and rather darker than 

 the body. 



This shell is very closely allied to H. sericea, of 

 Southern Europe, but it differs from that species iu 

 beins: destitute of the hirsute vesture. I found se- 

 veral specimens of jejuna, during an excursion some 



