COCHLOSTYLA OF MINDORO PROVINCE 385 



The nuclear whorls and the ground color of the postnuclear whorls 

 are white. Where the periostracum remains there seems to be a basal 

 film of straw color, upon which is superimposed a thin film of wood 

 brown, which is variously spirally banded with darker brown. On 

 the base these bandings become more emphasized. The interior of 

 the aperture and the peristome are white. Nuclear whorls 2.1, well 

 rounded, marked by incremental lines, and the last portion of the 

 last turn by the beginning of fine spiral striations. The postnuclear 

 whorls are strongly rounded and marked by fine incremental lines 

 and fine, closely approximated, spiral striations, which are conspic- 

 uously developed on all the turns, as well as on the base. The summit 

 of the whorls is appressed; the periphery feebly angulated; the base 

 inflated and strongly rounded. The aperture is broadly oval, almost 

 subcircular, oblique. The outer lip is moderately expanded and 

 reflected; the inner lip is decidedly oblique and almost straight, the 

 columellar side being somewhat excavated and covered by a thin 

 white callus, which also extends over the parietal wall. 



The type (U.S.N.M. no. 313568) was collected by Pedro de Mesa 

 at Tabukala near San Teodoro, Mindoro. It has 4.6 whorls and 

 measures: Length, 37.2 mm ; greater diameter, 47 mm ; lesser diameter,. 

 35.3 mm. 



This species strongly suggests Cochlostyla (Calocochlea) mclanocheila 

 in general size and the hydrophanous markings of the periostracum, 

 but the ground color of the nuclear whorls, the aperture, and expanded 

 peristome are white instead of dark. The aperture and columella 

 also are more oblique. I am therefore inclined to believe that it is 

 not merely a color phase of melanocheila. 



COCHLOSTYLA (CALOCOCHLEA) AOPTA (Clench and Archer) 



1933. Helicostyla {Calocochlea) aopta Clench and Archer, Papers Michigan 

 Acad. Sci., Arts, Letters, vol. 17, p. 542, pi. 57, fig. 3. 



"Shell imperforate, globose, rather solid. Nuclear whorl white, 

 gradually shading off into darkish, dull yellow on the body whorl. 

 From the nuclear whorl onward a brownish red subsutural band; 

 from about one and one-half whorls from the nuclear whorl a reddish, 

 gradually widening, gradually darkening band situated a short dis- 

 tance above the suture and continuing as a superperipheral band on 

 the body whorl; a broad, brownish band on the body whorl just below 

 the periphery. A brown circumcolumellar band present; aperture 

 white; peristome and columella white; a slight hydrophanous cuticle 

 appearing on the bod3 7 whorl in the form of axial streaks cutting across 

 the bands. Whorls 4, rounded, gradually increasing, and quite broad 

 in back of the peristome; spire somewhat elevated; aperture broadly 

 oblique and open; peristome rounded, moderately expanded and re- 

 curved; columella broad, slanting from the basicolumellar region 



1185—38 2 



