166 BULIiETIN 181, UNITED SfTATEiS NlATTOiNlAL MUSEUM 



spiral keel. Base well rounded and marked by 14 subequal spiral 

 keels, which are of about the same strength and spacing as those on 

 the spire, and by the continuation of the incremental lines. Umbilicus 

 moderately broad, marked by rather strong, riblike incremental lines. 

 Aperture oblique, broadly oval; peristome simple, thin. Operculum 

 corneous with central nucleus, the outer having the outer whorl 

 upturned and fimbriated. 



The specimen figured, U.S.N.M. No. 104651, is Lea's type of which 

 he says : 



"This shell was brought by Lfc. Humphreys from South America." 

 It has 5.5 whorls and measures : Height, 14.4 mm. ; greater diameter, 

 22.4 mm. ; lesser diameter, 17.3 mm. 



U.S.N.M. No. 104652 contains three additional specimens collected 

 by Cuming at Jumaco, western Colombia. U.S.N.M. No. 535747 con- 

 tains another specimen without locality data. 



In banding this species recalls G. nigrofasciatum (Miller), from 

 which its small size will at once distinguish it. 



CALAPEROSTOMA COUSINI (Jousseaurae) 



Plate 21, FiGimE 16 



1884. Cyclophorus cousini Jousseaxjme, Bull. Soc. Zool. France, 1884, p. 173, pi. 4, 



fig. 13. 

 1897. Amphicyclotns cousini Kobelt and Mollendokff, Naobrb. deutschen malak., 



Ges., vol. 29, p. 139. 

 1912. Amphicyclotus cousini Kobelt, Martini-Chemnitz Conchylien Cabinet, vol. 



1, sect. 19, part 3, p. 929, pi. 141, fig. 1. 



Shell openly umbilicated, depressed-helicoid, rather heavy with 

 traces of a chestnut brown periostracum, whitish. Upper whorls red- 

 dish, smooth ; those succeeding marked with more or less spiral sculp- 

 ture. The last has a broad shining white zone immediately below the 

 suture, upon which most of the periostracal remnants are conserved, 

 marked by spiral cords and axial riblets in the umbilicus. The shell 

 has 6 whorls, of which the upper increase regularly in size; the last 

 increases rapidly in size and is decurrent at the aperture. Aperture 

 almost circular, somewhat compressed dorsally, forming a slight 

 auricle at the posterior angle, shining, thin ; peristome smooth, thick, 

 slightly effuse, with a marked callus on the parietal wall. Height: 

 23 mm. ; greater diameter, 43 mm. ; lesser diameter, 35 mm. 



Type locality: Near Pailon, Esmeraldas, Ecuador. 



We have not seen this species and have given a translation of 

 Jousseaume's description from Kobelt's citation (loc. cit.) and have 

 copied Kobelt's figure. 



The strong ribbing on the umbilical wall allies this with C. hidalgoi 

 (Crosse), from which it is readily distinguished by its much larger 

 size. 



