LAND SHELLS OF GENUS OBBA FROM MINDORO 



349 



While the two references cited above report this subspecies from 

 Mindoro, Tablas, Romblon, and Sibuyan Islands, I wish now to 

 restrict it to Mindoro. Good and sufficient characters are to be found 

 in the abundant material before me from the other islands to warrant 

 their subspecific separation,- which will be done at some future time. 



The shell is depressed-helicoid with an acute peripheral keel and 

 moderately broad umbilicus. The nuclear whorls are flesh-colored 

 with a buffish tinge. The postnuclear turns are of flesh-colored 

 ground color, mottled, streaked, and variegated with various shades 

 of chestnut-brown. The base is flesh-colored and marked by a 

 broad interrupted spiral band of brown about one-third of the dis- 

 tance between the umbilicus and the periphery anterior to the periph- 

 ery. In addition to this, the malleations of the base are marked by a 

 weak wash of brown. The peristome is white and the inside of the 

 outer lip dusky brown with the darker band of darker color showing 

 through as a darker zone. The nuclear whorls are marked by fine 

 incremental lines and fine spiral striations, while the postnuclear 

 turns are also marked by rather strong incremental lines and mod- 

 erately strong incised spiral lines. They are also strongly malleated, 

 the malleations extending almost to the summit of the turns. In 

 addition to this, the surface is marked by very fine crisscross sculp- 

 ture, which is best expressed immediately behind the aperture. The 

 base is moderately convex, marked by moderately strong incremental 

 lines and moderately strong spiral striations, which are best expressed 

 in the umbilical area. In addition to this, it is covered with very 

 strong malleations, which extend from the periphery to the edge of 

 the umbilicus. The aperture is oval; the peristome is broadly ex- 

 panded and reflected, covering about one-third of the umbilicus at 

 the parietal wall. The inner lip bears a broad tooth on its middle. 



The present subspecies is represented in our collection by two 

 specimens from the Cuming collection, U.S.N.M. No. 116910. 

 These come from Mindoro without specific locality. They give the 

 following measurements : 



The present subspecies belongs to the strongly sculptured group. 

 It resembles 0. I. campoensis, from which it can at once be distin- 

 guished by its much smaller size and paler coloration. 



