THE CYCI.OPHORID LAHSTD M0LLUSK9 OF AMBEKIOA 201 



"Its nearest ally appears to be Neocyclotus Belli^ Beddome, but that 

 species is considerably larger, and lacks the coarse granules so con- 

 spicuous a feature in the present species." 



The type came from Colombia. Kobelt {he. cit.) says "Alejandria 

 near Medellin." 



The extremely lafge size of this species readily distinguishes it from 

 the other members of the subgenus. 



APEROSTOMA (AUSTROCYCLOTUS) KUGLERI. new species 

 Plate 28, Figures 1-3 



Shell helicoid, of pale brown color on the upper surface and buff 

 on the lower. There are also present axial streaks of irregular width 

 and spacing, of darker brown. The nucleus consists of 2 small, well- 

 rounded, smooth turns ; postnuclear whorls somewhat inflated, strongly 

 rounded, appressed at the summit and marked near the summit by 

 short axial rugae. Below this the usual sculpture of protractive and 

 retractive closely spaced ribs is present, which gives to the surface 

 a very regular granulated appearance. Suture well impressed. 

 Periphery well rounded. Base openly umbilicated, somewhat inflated, 

 well rounded, and marked like the spire, with the granulation extend- 

 ing over the edge of the umbilicus, but not over the entire surface. 

 Aperture circular, with a slight auricle at the posterior angle; peris- 

 tome simple, that of the inner lip much thickened and slightly 

 reflected; the outer thin. The callus on the parietal wall shows a 

 decided sinus near its junction with the columella. Operculum typ- 

 ically aperostomid, of about 6 whorls. 



The type, U.S.N.M. No. 515924, was collected by Kugler at Riecito, 

 District Acosta, Falcon, Venezuela. 



U.S.N.M. No. 515925 contains 21 topotypes, which show some varia- 

 tion in size. The largest and smallest yield the following measure- 

 ments : Height, 23.5 mm. and 16.8 mm. ; greater diameter, 32.5 mm. and 

 24.6 mm., respectively. 



In shape this species is nearest A. {A.) limellmn. It lacks, however, 

 the flattening near the summit of the whorls and is at once differen- 

 tiated from it by the sinus in the callus of the parietal wall. 



APEROSTOMA (AUSTROCYCLOTUS) CARABOBENSE, new species 



Plate 28, FrotntES 4r-6 



Shell small, helicoid, covered with a thin, yellowish, straw-colored 

 periostracum. The nucleus consists of 1.6 small, well-rounded, smooth 

 turns, forming a rather elevated apex. The postnuclear whorls are 

 decidedly inflated, well-rounded, slightly flattened at the summit and 



