COCHLOSTYLA OF MINDORO PROVINCE 



509 



chestnut-brown; the last whorl chestnut-brown. The shell is cov- 

 ered with a moderately thick periostracum, which is streaked, banded, 

 and sometimes fulgurated with retractively slanting axial streaks of 

 buff or orange-buff, alternating with brown and almost blackish- 

 brown bands, the darkest coloration always being on the last whorl 

 and the base of the last whorl being always darker than the posterior 

 portion of it. The aperture is decidedly bluish within, this colora- 

 tion extending to the inner edge of the periostracum, the outer ex- 

 panded peristome being dark, almost black, with an azurite reflec- 

 tion. The inner edge of the columella is like the interior of the aper- 

 ture, possibly a trifle darker, while the outer portion continues the 

 color of the peristome. Nuclear whorls 3; the first smooth and the 

 rest marked like the postnuclear turns, the space between grading 

 into these sculptures. The postnuclear whorls are appressed at the 

 summit, moderately well rounded, and marked by retractively slant- 

 ing lines of growth, which are somewhat irregular in width and spac- 

 ing. In addition the whorls are marked by the characteristic criss- 

 cross sculpture described for the species, which is present on base 

 and spire. The aperture is broadly oval; peristome is broadly ex- 

 panded and reflected, particularly so at the insertion of the columella 

 where it almost covers the umbilicus, leaving only a very narrow 

 chink. The parietal wall is covered by a moderately thick callus. 



This subspecies is most nearly related to the typical form but is 

 slenderer. 



1 Average. 



1 Greatest. 



•Least. 



