GYROTOMA. 



305 



multilineata, Say. 

 obruta, Lea. 

 occata, Hinds. 

 Proteus, Lea. 

 proxima, Say. 



Schiecleana, Phil. 

 silicula, Gould. 

 striata, Lea. 

 Troostiaua, Lea. 

 Yirginea, Say. 



Genus GYROTOMA, Shuttleworth. 



Shell ovate, turreted, whorls transversely silicate ; aper- 

 ture oblong; inner lip thickened, with a posterior cal- 

 losity ; outer lip thin, with a deep, narrow, posterior 

 fissure. 



Si/?i. Schizostoma, Lea, not Bronn. Melatoma, An- 

 thony, not Sicains. Schizocheilus, Lea. 



Ex. G. ovoidea, Shuttletvorth, pi. 32, fig. 4. Oper- 

 culum, G. ovoidea, fig. 4, a, 4, h. 



The fissure in the outer lip is wanting or obsolete in 

 the sub-genus Megara, the species of which, in other 

 respects, closely resemble those of Gyrotoma proper. 

 Both groups are American in their geographical distri- 

 bution. 



Species of Gryrotoma. 



al tills, Anthony. 

 Babylonica, Lea. 

 Budclii, Lea. 

 conica, Say. 

 constricta, Lea. 

 curta, Migh. 

 curvata. Say. 

 cylindracea, Migh. 



excisa, Lea. 

 Foremani, Lea. 

 funiculata, Lea. 

 iucisa, Lea. 

 laciniata, Lea. 

 ovoidea, Shuttl. 

 pagoda, Lea. 

 pyramidata, Shuttl. 



VOL. I. 



K R 



