160 UROCOPTIS OF HAITI. 



either uniform or marked into squarish blocks by brown 

 streaks at intervals. The last whorl has a cord-like basal keel. 

 The axis is slightly twisted, as in U. gruneri, at its root en- 

 circled by and passing into a short accessory lamella. Speci- 

 mens measure : 



Length 26.5, diam. 9.6 mm. ; whorls 7%. 



Length 24.6, diam. 9.3 mm. ; whorls 7. 



Length 25, diam. 8.8 mm. ; whorls 8. 



The C. strohmi of Maltzan and its "var." acupicta are 

 similarly colored, and measure : 



Length 32, diam. 10 mm.; whorls 8-9 (strohmi). 



Length 18-20, diam. 7 mm. (var. acupicta). 



34. U. ARCUATA (Weinland & Martens). PL 39. figs. 29, 30, 



31 ; pi. 40, figs. 36, 37, 38. 



Shell oblong-cylindric, the last whorl tapering, next earlier 

 4 whorls of about equal diameter, or the third or fourth from 

 the last may be slightly wider, those above tapering rapidly. 

 Surface nearly lustreless, flesh-colored, sculptured with white, 

 very strongly arcuate riblets, which are much stronger and 

 often joined in pairs near the sutures, occasionally split or 

 discontinuous in the middle of the whorl, and are often more 

 or less obsolete below the basal keel. The summit is narrowly 

 and concavely truncate. Whorls 7 to 8, someAvhat convex, 

 the suture impressed; last whorl typically shortly free in 

 front, having a strong basal keel, crenulated by the strise. 

 Aperture transversely oval, the peristome broadly expanding,, 

 reflexed. Internal column slightly twisted. 



Length 20.5, diam. 7 mm. ; whorls 7%. 



Length 22, diam. 8 mm. (W. & M. type). 



Length 23, diam. 7.3 mm. ; whorls 8. 



baiti: Neighborhood of Jeremie (Dr. Weinland, J. B. Hen- 

 derson). 



Cyl. arcuata W. & M., v. MARTENS, Malak. Blatt, vi, 1859, 

 p. 53. PFR., Monogr., vi, p. 360 ; Novit Conch., p. 257, pi. 65, 

 f . 1, 2. SOWERBY, Conch. Icon., pi. 6, f . 49. CROSSE, J. de C., 

 1891, p. 137, pi. 1, f. 8, 8 a. 



The typical form from Jeremie is nearly cylindrical, as in 



