230 CERION, GIIOUP VII. 



Fig. 62 is a copy of the type figure. Other specimens are smaller, 

 15x7 mill., and still others larger, with very broadly reflexed peri- 

 stome and 9^ whorls (fig. 63). 



Pfeiffer finally thought mumiola a form of C. mumia, an opinion 

 shared by Arango, and in which I agree. The only differences are 

 that mumiola is 'smaller, with fewer whorls ; but I have not yet seen 

 actual intergradation. According to Poey the flagellum is longer in 

 mumiola than in mumia. 



Dall reports it from the westernmost one of the Florida Keys, re- 

 marking that " the occurrence on Tortugas is probably the result of 

 transportation by sea drift. If living at Tortugas it would add a 

 new species to the fauna of the United States." 



C. SANZI ' Blanes ' P. & V. PL 29, figs. 54, 55, 56. 



Shell rimate, solid and strong, cylindric-conic. White, very 

 sparsely and inconspicuously mottled with pale blue-gray or brown ; 

 lusterless, the ribs rather glossy. Lower three whorls of about equal 

 diameter, those above forming a rather long cone terminating in an 

 obtuse apex. Whorls 10-llJ, the first smooth, the rest ribbed ; ribs 

 rather strong, narrow, separated by far wider interstices, 20-27 on 

 the penultimate whorl, frequently irregular or in part obsolete on the 

 last whorl, split on the base into an irregular striation. Aperture 

 irregularly ovate, the throat brown ; peristome reflexed, more or less 

 thickened, the terminations joined by a heavy parietal callus. Par- 

 ietal lamella deep within, strong and rather long; columellar tooth 

 well marked. 



Length 27, diam. 11^, length of aperture 10 mill. 



Length 23^, diam. 10^, length of aperture 9 mill. 



Cuba : Confites Key, Nuevitas, N. shore of prov. Puerto Principe. 



Cerion sanzi Blanes, PILS. & VAN., Proc. Acad. Nat. Sci. Phila. 

 1898, p. 478, fig. 9. 



This species has considerable resemblance to C. chrysalis, but dif- 

 fers in the strong development of the parietal lamella, which is long, 

 as in typical C. mumia, and in the narrower ribs. In some specimens 

 the interior of the aperture is mainly white, the brown appearing far 

 within. In one shell of the type lot there is a small accessory 

 denticle to the left of the main parietal lamella, and partially united 

 with it. This doubling of the parietal lamella occurs occasionally in 

 C. mumia and many other species. 



