THE CYCI^OPHO'RID LAND MOLLUSKS OF AMEHTCA. 245 



1897. Neocyclotus (Neoeyclotus) inca (pars) Kobelt and Moixendorff, Nachrb. 



deutschen malak. Ges., vol. 29, p. 137. 

 1923. Poteria (Neocyclotus) Manchetianum H. B. Bakes,, Oce. Pap. Mus. Zool. 



Univ. Michigan, No. 137, p. 44. 



Shell depressed-helicoid. The early whorls, denuded of the 

 periostracum, reddish ; the later reddish horn colored, the last oliva- 

 ceous on the upper surface. There is a narrow white zone at the 

 periphery and a broad dark olivaceous band covering the posterior 

 two-fifths of the base, the rest being horn colored ; interior of aper- 

 ture bluish white. The nucleus consists of 2 moderately large, well- 

 rounded whorls. The postnuclear whorls are strongly rounded and 

 marked by retractively curved, strong, small axial ribs, which are 

 smaller than the spaces that separate them. On the last half of the 

 last turn these riblets become much enfeebled and replaced by mere 

 rough incremental lines. The suture is narrowly deeply channeled. 

 Periphery very weakly angulated. Base broadly openly umbilicated, 

 inflated, well rounded and marked by the continuation of the axial 

 ribs, which grow considerably stronger on the umbilical wall. On 

 the last half of the last whorl they become fused and more or less 

 scalelike. Aperture circular, with a slight angulation at the pos- 

 terior angle ; peristome simple ; the outer lip thin, slightly reflected ; 

 the inner slightly thickened and also slightly reflected. The parietal 

 wall is covered by a rather thick callus, which renders the peritreme 

 complete. Operculum typically aperostomid, with about 10 whorls. 



The specimen described and figured is one of two, U.S.N.M. No. 

 98110, collected at Bahia, Brazil. It has 4.5 whorls and measures: 

 Height, 15.2 mm. ; greater diameter, 27.4 mm. ; lesser diameter, 19.7 

 mm. Height of aperture, 9.9 mm. ; diameter, 11.9 mm. 



The following additional specimens are in the National Museum 

 collections : 



No. 104450, five specimens from Bahia received from Moricand; 

 No. 307417, one specimen labeled "Brazil"; No. 381893, one specimen 

 from the Amazon Valley. This species closely resembles A. (A.) 

 peruense but is readily differentiated from it by its deeply incised 

 narrow suture. 



APEROSTOMA (APEROSTOMA) PERUENSE, new species 



Plate 35, Figures 10-12 



Shell very depressed-helicoid, almost planorbid; the upper surface 

 dark horn colored. There is a light white band immediately above 

 the periphery and a broad brilliant chestnut-brown zone immediately 

 below the periphery. There is also a second, very narrow brown 

 band separated from the broad band by a space about twice as wide 

 as the narrow brown band. The rest of the base is horn colored. 



