UROCOPTIS, S. G. GONGYLOSTOMA. 225 



96. U. DIFFICULTOSA (Arango). 



Shell rimate, cylindric-turrete, rather solid, glossy, obso- 

 letely eostulate, pale straw-colored; spire shortly truncate, 

 the suture not crenulate. Whorls remaining 10, rather flat, 

 the last subcarinate at the base, not protracted. Aperture 

 oval, the peristome shortly expanded, the left margin less so. 

 Internal column ornamented with two strong folds. Length 

 11, diam. 2.75 mm. (Arango). 



Cuba. 



Cyl. difficultosa ARANGO, Proc. A. N. S. Phila. 1882, p. 107. 

 Cyl. difficilis CROSSE, Journal de Conchy!., 1890, p. 218 

 (emendation of difficult osa) . 



Differs from C. concreta by the riblets, non-solute last 

 whorl, and form of the internal column (Arango). 



97. U. LAVALLEANA (Orbigny). PI. 54, figs. 85, 86. 



Shell much lengthened, subcylindric, thin, fragile, trans- 

 parent, very smooth. Spire very much lengthened, cylindric 

 anteriorly, attenuate behind, and truncate at the summit, 

 which is acute in the young; 'composed of 12 quite narrow, 

 convex whorls; the last whorl produced laterally near the 

 mouth, longitudinally striate, carinate beneath. Whorls 

 separated by a rather deep suture, which is regularly crenu- 

 late. Aperture free, lateral, oval, oblique, with thin, slightly 

 reflexed, continuous peristome. Color uniform light brown. 

 Length 21, diam. 4 mm. (Or&.). 



Western Cuba: Cerro de Cuzco (MM. Auber and Delatre). 

 Central Cuba: Sitio Quemado and Guinia de Miranda, dis- 

 trict of Trinidad, prov. Santa Clara (Gundlach). 



Pupa lavalleana ORB., in Sagra, Hist. Cuba, Moll., i, p. 183, 

 pi. 12, f. 18-20. Cyl. lavalleana Orb., PFR., Monogr., ii, p. 

 372; iv, 693; vi, 362; Conchyl. Cab., p. 17, pi. 9, f. 18-25. 

 ARANGO, Contrib., p. 106. fCyl. lavalliana SOWB., C. Icon., 

 pi. 7, f. 56. 



The original description is given, and the original figures 

 are copied, pi. 54, figs. 85, 86. The locality given by Orbigny, 

 ''Cerro de Cuzco," is apparently the mountain of that name 

 near Cayajabos, in Pinar del Rio. The internal structure 

 of this form is unknown. 



