164 BTJLLiETinsr 181, UlSPITED SfTATES NiAn?TOiisnAa:. ivrusiE'UM 



The impressed suture allies this species with G. chanchapoyasense 

 (Da Costa), from which the smaller size and feebler sculpture will 

 readily distinguish it. 



CALAPEROSTOMA PITTIERI, new species 

 Plate 21, Figuees 7-9 



Shell depressed-helicoid ; color of periostracum ? The denuded shell 

 is white, the early whorls reddish. The nucleus consists of a little more 

 than one smooth turn, the succeeding turns being marked by spiral 

 cords, which are of almost equal strength and spacing. Of these, 16 

 are present between the summit and the suture on the last two turns. 

 The spaces separating these cords are considerably wider than the 

 cords. In addition to this the whorls are marked by fine, closely spaced, 

 hairlike incremental lines. Suture rendered inconspicuous by the 

 appressed summit. Periphery well rounded. Base somewhat inflated, 

 strongly rounded and marked by 17 spiral cords equaling those on the 

 spire. In addition to the spiral cords the base also shows the incre- 

 mental lines equaling those on the spire. The umbilicus is broadly 

 open and marked by riblike incremental lines and is free from spiral 

 cords. Aperture decidedly oblique, subcircular, feebly auriculated at 

 the posterior angle; peristome simple, that of the parietal wall covered 

 with a thick callus. Operculum ? 



The type, U.S.N.M. No. 523513, was collected by H. Pittier in 

 Panama. It has 6 whorls and measures: Height, 18.0 mm.; greater 

 diameter, 32.3 mm. ; lesser diameter, 24.4 mm. 



U.S.N.M, No. 228670 contains 4 topotypes, the smallest of which 

 measures : Height, 15.9 mm. ; greater diameter, 27.3 and lesser diameter, 

 10.3 mm., and has 5.8 whorls. The largest has 6 whorls and measures : 

 Height, 20.1 mm. ; greater diameter, 33,8 mm.. ; lesser diameter, 26.3 mm. 



This species differs from C. hourcleri (Pfeiffer) in being much 

 larger and in having the summit of the whorls appressed. 



CALAPEROSTOMA NIGROFASCIATUM (Miller) 



Plate 21, Figukes 13-15 



1879. Cyclophorus nigrofasciatus Muxer, Malak. BUitter, new ser. vol. 1, p. 142, 



pi. 7, fig. 5. 

 1897. Amphicy Glottis nigrofasciatus Kobext and Mollendorff, Nachrb. deutschen 



malak. Ges., vol. 29, p. 139. 

 1912. Amphicyclotus nigrofasciatus Kobext, Martini-Chemnitz Conchylien Cabinet. 



vol. 1, sect. 19, p. 921, pi. 138, figs. 3-5. 



Shell rather large, helicoid. "When decorticated white with the early 

 whorls rose-red. In the specimen before us some of the periostracum 

 remains and shows the broad dark chestnut brown band a little dis- 

 tance below the summit and a narrow thread covering the rib immedi- 



