UROCOPTIS, S. G. GONGYLOSTOMA. 235 



113. U. VOLUBILIS (Morelet). 



"Shell cylindric-subulate, slightly truncate, smooth, pel- 

 lucid whitish. Whorls 19, a little convex, the last disjoined, 

 cylindric, forming an obrotund, oblique aperture; peristome 

 free throughout, a little thickened, narrowly reflexed. 

 Length -15, diam. 3 mm." (Morel.). 



Western Cuba: Pan de Guajaybon (Morelet), in Pinar 

 del Rio. 



Cyl. volubilis MOREL., Testacea Noviss., i, p. 11, no. 17 

 (1849). PFR., Monogr., iii, p. 576. ARANGO, Contrib., p. 

 115. 



The internal structure of the true Mt. Guajaybon volubilis 

 is apparently unknown. Pfeiffer placed saxosa Poey as a 

 synonym of volubilis, but in Monographia, vi, p. 372, he says 

 that the axis of the latter has a weak spiral thread. 



114. U. CRASSILABRIS (Arango). 



Shell rimate, subcylindric, rather solid, obliquely remotely 

 lirate, brownish; spire shortly truncate, the suture subcrenu- 

 late. Whorls remaining 11, rather flat, the last obsoletely 

 carinate, shortly solute; peristome white, reflexed, especially 

 the right margin. Internal column having one weak lamina 

 below. Length 12.5, diam. 3 mm. 



Cuba. 



Cyl. crassilabris AR., Proc. A. N. S. Phila. 1882, p. 108 

 (June 27, 1882). 



Section Tomelasmus Pils. & Van., 1898. 



P. & V., Proc. A. N. S. Phila. 1898, pp. 271, 276. Type 

 U. torquata (Morel.). Misquoted Tomelasmus, Zool. Record 

 for 1898, Moll., p. 60. 



This group as originally defined must be abandoned, as it 

 is now known that the reduction of the lamellae to a single 

 sub-basal one occurs in various phyla. The section is here 

 retained for a number of groups, perhaps more allied to one 

 another than to species of other sections, but still so hetero- 

 geneous as to make a general definition almost impracticable. 



