COCHLOSTYLA OF MINDORO PROVINCE 517 



This is a very dark-colored ovate form, which suggests Cochlostyla 

 (Chrysallis) aspersa melanogaster but lacks the dark basal coloration. 



COCHLOSTYLA (CHRYSALLIS) ASPERSA ILOGANA Bartsch 



Plate 113, Figure 8 



1932. Cochlostyla (Chrysallis) aspersa ilogana Bartsch, Journ. Washington 



Acad. Sci., vol. 22, p. 342. 



1933. Helicostyla (Chrysallis) mindoroensis parallaxis Clench and Archer, 



Papers Miehigan Acad. Sci., Arts, Letters, vol. 17, p. 550; in part. 



Shell very elongate and regularly ovate, all but the last whorl pale 

 chestnut-brown, that one very dark brown, almost black. The shell 

 is covered with a rather strong periostracum, which is axially re- 

 tractively streaked with zones of dull buff, these zones varying ma- 

 terially in width and permitting the ground color of the shell to appear 

 in the interspaces. The light zones are not at all regular but vary 

 from straight bands to figurations. The base is usually slightly 

 darker than the posterior half of the last whorl, and here the bands 

 frequently assume an orange-buff tinge. The aperture is pale blue 

 within; the broadly expanded peristome is almost black. There is 

 a bluish triangle at the inner edge of the insertion of the columella. 

 Nuclear whorls 2.8, the first smooth, the rest gradually assuming the 

 postnuclear sculpture. The postnuclear whorls are slightly shouldered 

 at the summit, almost flattened, the last one is feebly angulated at 

 the periphery and has the base strongly protracted. They are 

 marked by retractively curved, almost flattened, threadlike lines of 

 growth, which extend on the last whorl to the umbilical chink. In 

 addition they are marked by obsolete spiral striations and the usual 

 crisscross microscopic sculpture. The aperture is elongate-oval; 

 the peristome is broadly expanded and reflected, that of the inner Up 

 almost covering the umbilicus. The parietal wall is covered by a 

 rather strong callus. 



The type (U.S.N.M. no. 313706) was collected by Pedro de Mesa 

 at Camorong, Abra de Hog, Mindoro. It has 6.8 whorls and meas- 

 ures: Length, 66.3 mm; greater diameter, 31.7 mm; lesser diameter, 

 25.6 mm. 



Thirty-eight topotypes (U.S.N.M. nos. 313707, 313659, and 313662) 

 yield the additional information shown on the following page. 



