THE NAUTILUS. 47 



upper half of peristome white. Peristorne well expanded and re- 

 flexed. Axis encircled by three lamellae, the lowest denticulate 

 above the penultimate whorl, moderately enlarged in the middle and 

 extending to the last whorl. The upper lamella, compressed at 

 first, becomes cord-like and disappears in the penultimate whorl ; the 

 intermediate lamella smallest and thread-like above. 



Long. 24, diam. 5.8, apert. diam. 5.2 mm. Whorls 11. 



Long. 20, diam. 5, apert. diam. 4.6 mm. Whorls 9.5. 



Long. 22, diam. 5, apert. diam. 5 mm. Whorls 10.5. 



Central Cuba; Sierra de Matahambre at Las Llanadas, in the 

 district of Mayajigua, province of Santa Clara. 



This species is intermediate between U. cioniscus and U. fallax, 

 but is easily distinguished by its shape, color, and chiefly by the 

 columellar axis. 



UROCOPTIS (GONGYLOSTOMA) FALLAX, n. sp. 



Shell rimate, cylindric, the upper third tapering to a rather wide 

 truncation ; thin ; dull yellowish with occasional irregularly spaced 

 brown streaks. Surface lusterless, sculptured with narrow arcuate 

 riblets separated by much wider intervals. Whorls 911, convex, 

 the last purplish brown, shortly free in front, rounded below, with an 

 almost obsolete cord around the base. Aperture nearly round, 

 brown within ; peristome, upper wall and columella white. Peris- 

 tome broadly expanded and reflexed. Axis stout and encircled by 

 three sub-equal compressed lamellae, the lowest largest in penulti- 

 mate whorl and smallest in the upper whorls where the upper 

 lamellae dominate ; lower lamella denticulate above. 



Long. 25, diam. 6.2, apert. diam. 6. Whorls 11. 



Long. 20, diam. 6, apert. diam. 5.6. Whorls 9. 



Long. 23, diam. 6, apert. diam. 6. Whorls 10.5. 



Central Cuba; Vereda de el Alunado, through the Sierra de 

 Jatibonico in the district of Mayajigua, Prov. of Santa Clara. 



Superficially resembling U. intermedia but differing chiefly in its 

 more widely spaced riblets and in its axial structure. From U- 

 transitoria it differs by its stouter form, sculpture and columellar 

 axis. 



UROCOPTIS (GONGYLOSTOMA) DILATATA, n. sp. 



Shell rimate, cylindric, slightly swollen, the upper third tapering 



