OCHRODERMA. 325 



densely striate vertically. The striation then becomes some- 

 what arcuate, coarser, and thread-like, but on the last three 

 whorls the threads give place to low wrinkles of growth. 

 Whorls 8y 2 , quite convex, separated by a deep suture, the 

 last whorl inflated. Aperture slightly oblique, ovate; outer 

 and basal margins forming an evenly curved arc, thin, not 

 arched forward. Columella calloused, sinuous, strongly con- 

 cave above, obliquely truncate at base. Parietal wall with- 

 out perceptible callus. Length 18, diam. 7.8, length of aper- 

 ture 6.5 mm. 



Venezuela: Caracas (F. Cocking, in R. Swift coll.). 



This is an extraordinary species, unlike other known forms 

 by the contraction and sharp sculpture of the upper part of 

 the spire and the very sinuous columella. It is larger than 

 any other Leptinaria except L. perforata Pfr. 



Genus OCHRODERMA Ancey. 



Ochroderma ANC., Le Naturaliste, iii, June, 1885, p. 93, for 

 Tornatellina gigas. 



She'll imperforate, ovate-turrite, solid, with convexly conic 

 summit and rather flattened whorls; covered with an oliva- 

 ceous or greenish-yellow cuticle. Whorls few, 5 1 /-> to 7 in 

 known species, the first 2y 2 or 3% composing the embryonic 

 shell, separated from the following by a forwardly-oblique 

 wrinkle or line ; the following whorls with normally subob- 

 lique growth-lines. Aperture ovate, armed with a deeply en- 

 tering parietal lamella; columella twisted and truncate at 

 base ; outer lip usually with some trace of an entering ridge 

 in the throat. 



Jaw vertically striate (in 0. martensi] . Radula Stenogy- 

 roid, the central tooth very small, unicuspid, laterals and 

 marginals tricuspid. Anatomy otherwise unknown. 



Type 0. gigas. Distribution, Caroline Islands and Cocos 

 Island, in the Pacific about 550 miles southwest of Panama. 



This genus differs from Leptinaria and Neosiibulina by the 

 structure of its embryonic whorls. The summit is convexly 

 conic rather than subglobose, and the latter part of the last 

 embryonic whorl has forwardly oblique striation. much as in 



