150 UROCOPTIS OF HAITI. 



the middle, the upper third strongly tapering to a narrow 

 truncation; the terminal plug nearly flat and vertical. Sur- 

 face lustreless, pale brown, streaked with white, sculptured 

 with close, arcuate, thread-like white striae, which unite by 

 twos or threes into raised white nodules along below the 

 suture. Whorls 8% to 11, slightly convex, the last very 

 shortly or not free in front, pinched into a very strong cord- 

 like keel beneath. Aperture obliquely short-oval, angular at 

 the outer-basal part, channelled within; the peristome con- 

 tinuous and free or barely in contact above. Internal axis 

 somewhat twisted throughout; in the last whorl a spiral la- 

 mella revolves close to its root, extending more than a whorl 

 inward, its lower end visible in the aperture as a low white 

 fold. 



Length 21, diam. 7.3 mm. ; whorls 9. 



Length 21.5, diam. 6.2 mm. ; whorls 11. 



Length 19, diam. 6 mm.; whorls 9 (Pfeiffer's type). 



Haiti: Rep. of S. Domingo, at Azua and Las Charcas (A. 

 Salle) ; Rep. Haiti, at Thomazeau (Henderson & Simpson). 



Cyl. monilifera PFR., Zeitschr. f . Malak., 1850, p. 74 ; P. Z. 

 S., 1851, p. 148 ; Conchyl. Cab., p. 10, pi. 2, f . 1-3 ; Monogr., 

 iii, p. 568. CROSSE, Journ. de Conchyl., 1891, p. 140. 



The suture is white-beaded below, and the end of the apical 

 plug flattened, as in U. adamsiana, but the thread-like striae 

 and continuous peristome of U. monilifera readily differen- 

 tiate the two species. The accessory basal lamella is much 

 longer than in U. adamsiana. The empty whorl generally 

 persists some distance beyond the terminal plug, which is 

 usually not visible without breaking away a portion. 



24. U. RUDIS (Weinland). 



Shell rimate, truncate, slightly diaphanous, fleshy- whi tish ; 

 irregularly and rudely crispate, with close, whitish, undu- 

 lating, sometimes confluent striae. Suture crenated with 

 sparse, rather coarse lobules. Whorls remaining 9, rather 

 flat, the last hardly narrower than the preceding, slightly 

 produced, angulated by a compressed, denticulate keel. 

 Aperture a little oblique, nearly circular, a little straightened 



