UNIVERSITY 



246 CERION, GROUP X. 



a. Species from Abaco. 



b. White; ribs regularly strong and close; umbilical area 



small. C. abacoense, p. 246. 



b 1 . White or mottled above ; ribs wider apart or irregularly 



spaced ; umbilical area larger. C. maynardi, p. 246. 



a 1 . Species from Rum Key. 



b. Entire shell ribbed. C. album, p. 247. 



b\ Whorls of the cone smooth. C. lentiginosum, p. 248. 



C. ABACOENSE Pilsbry and Vanatta. PI. 37, figs. 58, 59. 



Shell cylindrical, solid and strong, entirely white. Latter three 

 whorls of about equal diameter, preceding one slightly smaller, those 

 earlier rapidly tapering to form a short cone ; apex obtuse. Sculp- 

 tured with very regular, rather close, strong and nearly straight rib- 

 lets, as wide as, or narrower than the interstices, numerous (31-38 

 on last whorl); part of the riblets generally splitting on the base; l 

 to 1J nepionic whorls free from riblets, and those of the following 

 several whorls very fine, though distinct. Whorls 9| to 11^, slightly 

 convex, the last ascending as usual. Sutures well-marked. Um- 

 bilicus a nearly straight suture terminating in an almost closed axial 

 chink; umbilical area (back of columellar lip) small, with a bound- 

 ing furrow below. 



Aperture vertical, brought forward almost to anterior level of the 

 cylinder; rounded, nearly as wide as high, obliquely truncate above. 

 Peristome well reflexed, recurved, its face thickened and convex ; 

 parietal callus heavy, but thin at its outer edge. Axial fold moder- 

 ate, parietal fold deep seated, low, and rather long. 



Length 34, diam. 13; alt. of aperture 12 mill, (largest specimen). 



Length 27^, diam. 13; alt. of aperture 11| mill, (shortest speci- 

 men). Bahamas: Abaco. 



G. abacoense P. and V., Proc. A. N. S. P., 1895, p. 209 ; 1896, 

 p. 332, pi. 11, f. 11. ? Strophia mumia var.? W. G. BINNEY, Ann. 

 Lye. Nat. Hist, of N. Y., x, p. 348 ; Ann. N. Y. Acad. Sci., iii, p. 

 101, pi. 7, f. B (dentition). 



Resembles G. album Mayn. of Rum Key, but has a much smaller 

 umbilical area and a thicker lip. It is closely related to G. may- 

 nardi. 



C. MAYNARDI Pilsbry and Vanatta. PI. 37, figs. 64, 65. 



Shell large, strong, cylindrical, white or fleshy in the intervals 



