LAND SHELLS OF GENUS OBBA FROM MINDORO 



363 



The present species is most nearly related to Obba planulata vara 

 deroana, from which it differs by its much rougher sculpture and its 

 somewhat smaller size. 



OBBA PLANULATA VARADEROANA, new subspecies 



Plate 92, Figure 4 



The shell is large, depressed-helicoid, almost lenticular, with a 

 conspicuous carina at the periphery. There is an indication of a 

 median color band consisting of a series of spots, which disappear 

 upon the last half turn. The rest of the upper surface is blotched 

 and spotted and streaked with brown; the pattern is best understood 

 by consulting our figure of the upper surface of the shell. The last 

 third of a turn is darker than the rest and the colored elements more 

 fused. The base is soiled flesh-color, with the outer third vermic- 

 ulated with pale brown, the inner border of which terminates in a 

 more or less conspicuous band. The peristome is buff with a dusky 

 wash. The postnu clear whorls are malleated on the anterior half, 

 the malleations extending to the peristome on the last whorl on both 

 the upper and lower surface. The whorls are also marked by incised 

 spiral lines, which are stronger on the early postnuclear whorls and 

 the base than on the upper surface of the last whorl. The incremental 

 lines are rather coarse. The aperture is large and rather broad; the 

 peristome is thickened and reflected, and almost half covers the 

 umbilicus. The tooth on the inner lip is strong. 



Type.— The type, U.S.N.M. No. 382703, and eight adult specimens, 

 U.S.N.M. No. 256424, were collected by me at Varadero, northeastern 

 Mindoro. The type has 5 whorls, and measures: Height, 15.2 mm; 

 greater diameter, 33 mm; lesser diameter, 27.6 mm. 



Remarks.- — The nine specimens jdeld the following comparative 

 measurements: 



Type. 



