CUBAN SUBFAMILY CHONDROPOMINAE — TORRE AND BARTSCH 369 



are equal to the axial riblets in strength. The junction of these two 

 elements forms slender nodules, while the spaces enclosed between 

 them form squarish pits. Suture rendered conspicuously crenulated 

 by the toothlike projection at the summit. Periphery well rounded. 

 Base moderately long, well rounded, moderately, broadly umbilicate, 

 marked by the continuation of the axial riblets and spiral threads, 

 which are a little stronger than those on the spire. The umbilical 

 wall is marked by five rather strong spiral cords as well as the feeble 

 continuation of the axial riblets. Aperture oval; peristome double 

 all around; outer peristome expanded obliquely all around, a trifle 

 narrower on the columellar wall; inner peristome also expanded 

 and reflected ; at the posterior angle there is a slight auriculation, and 

 here several lamellae are present between the inner and outer peri- 

 stome. Operculum thin, paucispiral with the nucleus intermediate 

 between subcentral and marginal, the major portion covered with a 

 thin, finely granular deposit. 



The specimen described and figured, U.S.N.M. no. 493256, is one 

 received from Dr. de la Torre and collected by Cisneros at Cabo Cruz, 

 Oriente Province. This has 7.6 whorls and measures : Length, 15.0 

 mm ; greater diameter, 6.8 mm ; lesser diameter, 5.4 mm. 



The species ranges along the south coast from Ojo de Agua to 

 Manzanillo. 



CHONDROPOMA (CHONDROPOMORUS) DILATATUM (Gundlach) Pfeiffer 



Shell elongate-conic, with the ground color flesh-color or horn 

 color, marked by interrupted spiral bands of brown, which vary 

 from inconspicuous to very decided chestnut brown in color, and 

 which also vary very materially in width; peristome whitish, rayed 

 with brown; the interior of the aperture varies with the coloration 

 of the outside ; there is also a brown line following the suture on the 

 apex of the shell. Nuclear whorls almost 2, well romided, smooth 

 except the last portion of the last turn, which shows the beginning 

 of the postnuclear sculpture. Postnuclear whorls strongly rounded, 

 marked by very slender, poorly developed, retractively slanting axial 

 riblets; of these, at quite regular intervals, several become fused 

 at the summit to form conspicuous denticles. The strength of these 

 denticles varies materially in the different races. The spiral 

 sculpture consists of quite closely spaced threads, which in some 

 of the races are of about the same strength as the axial riblets, while 

 in others they are weaker; the junctions of the axial riblets and the 

 spiral threads scarcely form nodules, while the spaces enclosed be- 

 tween them are moderately well impressed pits. Suture well con- 

 stricted. Periphery subangulate. Base short, well rounded, openly 



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