30 



ruptly bent backwards at the carination on the upper edge 

 of the volution which marks the notch in the upper angle 

 of the aperture. 



Length *18 of an inch. 



Locality. — Spergen Hill. 



\/ Bulimella elongata. — Shell extremely elongate ; volu- 

 tions seven or eight (perhaps nine), somewhat rapidly as- 

 cending, moderately convex, the greatest convexity a little 

 above the middle, last one slightly ventricose ; suture dis- 

 tinct, an undefined angular elevation below, corresponding 

 to the notch in the lip ; surface nearly smooth ; direction of 

 the stria3 scarcely visible. 

 Length *50 of an inch. 

 Locality. — Spergen Hill, la. 



HOLOPEA, Hall. 



* Holopea Proutana. — Shell ovate-conical ; spire some- 

 what rapidly tapering ; volutions about six ; moderately 

 convex, last one ventricose, sub-angular in the direction of 

 the suture line, and obliquely extended below ; suture sharp- 

 ly defined ; aperture round-ovate, oblique on the upper side ; 

 pillar lip slightly reflexed in the umbilical region ; umbili- 

 cus none ; surface marked by fine striae parallel to the lines 

 of growth. 



Length *062 to *50 of an inch. 



Locality. — Spergen Hill, la. ; Alton, 111. 



NATICA, Adanson. 



^' Nattca Littoxana. — Shell short, sub-fusiform ; spire de- 

 pressed-conical ; volutions about four, rapidly increasing 

 from the apex, the last volution symetrically ventricose and 

 prolonged below ; suture not strongly marked ; aperture 

 narrow-ovate, sharp above, and narrowing near the front ; 

 outer lip thin ; inner lip thickened ; surface striated. 



Height '25 ; diameter *19 ; last volution *17 of an inch. 



Locality. — Bloomington, la. 



