LAND SHELLS OF GENUS OBBA FROM MINDORO 371 



OBBA PLANULATA CAGURAYANA, new subspecies 



Plate 93, Figure 5 



The shell is broadly conic and weakly angulated at the periphery 

 of the last whorl. The first nuclear whorl is pale buff, the rest deeper 

 buff. The first postnuclear whorl is chestnut-brown, which is also 

 the color of the remaining turns. In addition to this, the whorls 

 are marked by more or less zigzag or interrupted axial lines and dots 

 of flesh-color. There is a narrow median brown band on all the 

 whorls, which extends to the peristome on the last turn. The base 

 is pale brown with a deeper brown band about one-third of the 

 distance between the periphery and the umbilicus anterior to the 

 periphery. The postnuclear whorls in the young shell are strongly 

 keeled, and the succeeding turns drop below this keel to which they 

 are appressed. All but the last one and one- third turns are feebly 

 malleated on the anterior half. The postnuclear whorls are marked 

 by rather regular, weak, retractively curved incremental lines and 

 exceedingly fine spiral striations on the upper surface. On the base 

 of the last whorl these spiral striations become more pronounced. 

 The aperture is broadly oval; the peristome is strongly reflected and 

 thickened, covering half the umbilicus at the parietal wall. The 

 inner lip has a conspicuous tooth on its middle. 



Type.— The type, U.S.N. M. No. 382887, was collected by C. 

 Canonizado at Caguray. It has 5 whorls, and measures: Height, 

 13.6 mm; greater diameter, 26.9 mm; lesser diameter, 21.3 mm. 



Remarks. — This species most nearly resembles Obba planulata man- 

 garina, from which it can at once be distinguished by its much 

 smoother sculpture. 



c 



