New Species of S7iclls. 167 



times unduly enlarged at the expense of one or more of the re- 

 maining ones, thus giving the shell unusual gibbosity. The shell 

 is also crossed by numerous revolving elevated lines, two of which 

 are more prominent than the others, especially at the point where 

 they cross the varices. The uppermost of these ridges supports the 

 series of tubercles already mentioned, the other is occasionally el- 

 evated at irregular intervals into a few tubercles of much smaller 

 size than those upon the upper. The varices are transversely ru- 

 gose. Aperture ovate, extending upwards into a deeply hollowed 

 channel, the remains of which are very apparent on each of the 

 last three whorls, at the junction of the varix with the suture. Right 

 lip thickened and strongly denticulate. Columella transversely 

 wrinkled. Color yellowish white or light fawn, obscurely and ir- 

 regularly clouded with reddish brown, and the last whorl is crossed 

 by three series of brownish dots or interrupted lines, of which the 

 uppermost two follow the series of tubercles, and the other crosses 

 the front of the shell, near the upper part of the aperture, and is 

 there more apparent than elsewhere : length, 1.9 inches, breadth 

 1.4 inches. 



Divergence of spire, measured at the varices 80°. 



Habitat. — Unknown, probably some portion of the Pacific or 

 Indian Oceans. 



Remarks. — This interesting species of Ranella, which seems 

 to have been unknown to, or overlooked by all the writers upon 

 this genus, bears much relation to the R. bufonia (Gmel.) Lam., 

 but is clearly distinct. The spire is more obtuse, its tubercles 

 which are more elevated and pointed, are remarkable for their hor- 

 izontal compression, and for their frequent distortion ; its surface 

 is not pitted or punctured as in the R. bufonia, while the wrinkles 

 which cross the shell are much less developed and of quite a differ- 

 ent character from those of that species. The R. margaritala 

 Deshayes, also approaches our species in some respects, but differs 

 decidedly in the character of its tubercles, and in its surface which 

 is throughout finely granulated. It is moreover of a much darker 

 color. 



