344 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 85 



The type, U.S.N.M. no. 499609, comes from the west side of the 

 center of the main range, south of the road leading to the Presidio. 

 It has a little more than 4 wliorls remaining and measures: Length, 

 20.8 mm; greater diameter, 12.1 mm; lesser diameter, 9.8 mm. 



CHONDROPOMA (CHONDROPOMA) VESPERTINUM BIBIJAGUENSE, new subspecies 



Plate 30, Figure 16 



Of this race Bartscli collected two not quite perfect specimens on 

 the west side of the central part of the Sierra Bibijagua, which are 

 so different from the others that they must be noticed. Here the shell 

 is as thin as paper, translucent, flesh-color, and marked with very 

 conspicuous, almost continuous, interrupted spiral lines of brown. 

 The columella and the first of the remaining turns are brown; the 

 peristome is white. 



The type, U.S.N.M. no. 499G11, has a little more than 4 whorls 

 remaining and measures: Length, 16.4 mm; greater diameter, 11.2 

 mm ; lesser diameter, 8.8 mm. 



CHONDROPOMA (CHONDROPOMA) VESPERTINUM COLOMBENSE, new subspecies 

 Plate 30, Figuke 15 



This race comes from the northwestern end of the Sierra Colombo. 

 It is a dark race like typical G. {C.) vespertinum vespertinum., but 

 smaller and slenderer. 



The type, U.S.N.JNI. no. 493144, has 5 whorls remaining and meas- 

 ures: Length, 17.0 mm; greater diameter, 9.6 mm; lesser diameter, 

 7.3 mm. 



CHONDROPOMA (CHONDROPOMA) WILCOXI Pilsbry and Henderson 



Plate 31, Figure 7 



1912. Chondropoma tvilcoxi Pilsbky and Henderson, Nautilus, vol. 20, p. 45. 



Shell elongate-conic; when truncated elongate-ovate; pale brown, 

 with interrupted si)iral bands of brown a trifle darker than the 

 ground color. The dots composing these bands are rather distantly 

 spaced and are ai'ranged in both axial and spiral series. The inter- 

 rupted spiral bands of brown are only feebly indicated on the base. 

 The peristome is a little paler than the ground color. Nuclear 

 whorls 2, dark chestnut-brown, the first one being more intensely so 

 than the rest, smooth, strongly rounded, forming an almost flattened 

 apex, the last portion of the last turn shows traces of the beginning 

 of the axial threads. Postnuclear turns well rounded, narrowly 

 shouldered at the summit, marked by slender, retractively slanting, 

 narrow axial riblets, which extend prominently to the summit; in 



