370 BULLETIN 100, UNITED STATES NATIONAL MUSEUM 



to the last whorl. The postnuclear whorls are marked by rather rough 

 and somewhat irregular incremental lines and moderately strong, well- 

 incised, spiral striations. The base of the last whorl is malleated; the 

 impressed portions being brown lend to it a peculiar color pattern. 

 It is also marked by the continuations of the incremental lines and 

 spiral striations, which are a little stronger than those on the upper 

 surface. Aperture ovate; peristome broadly expanded and reflected, 

 half covering the umbilicus at the parietal wall. The inner lip has a 

 conspicuous tooth on its middle. 



Type.— The type, U.S.N. M. No. 382709, comes from the Quadras 

 collection and was collected at Sitio, Lalangan, Mangarin, southern 

 Mindoro. It has 4.8 whorls, and measures: Height, 14.9 mm; 

 greater diameter, 28 mm; lesser diameter, 21.5 mm. 



Remarks. — This shell in shape and coloring resembles most nearly 

 Obba planulata cagurayana, with which it is also geographically most 

 nearly approximated, but it is at once distinguished by its much 

 rougher sculpture both on spire and base. 



OBBA PLANULATA VERDENSIS, new subspecies 



Plate 93, Figure 6 



The shell is depressed-helicoid. The early whorls are of dark buff 

 and the later of flesh-colored ground color. A conspicuous median 

 bright chestnut-brown band, which is almost complete, is present on 

 the upper surface. A second, but a little more interrupted, band is 

 present at the angulated periphery. In addition to these bands, the 

 upper surface of the whorls is marbled and axially streaked with 

 brown. The basal surface is flesh-colored with an interrupted zone 

 of brown about as distant from the periphery as the median band on 

 the upper surface of the whorl is distant from it. The peristome is 

 white. All but the last postnuclear whorls are malleated on the 

 anterior half of the turns. In the same area they are also marked 

 by rather strongly incised spiral lines, but these weaken decidedly on 

 the last whorl. The incremental lines are irregular and rather coarse, 

 even on the lower surface. On the base the incised spiral lines are 

 stronger than on the upper surface. The aperture is large, oval, 

 with the peristome thickened and reflected, covering one-third of 

 the umbilicus at the parietal wall. The median basal tooth of the 

 inner lip is quite strongly developed. 



Type.— The type, U.S.N.M. No. 256550, was collected by Col. 

 Edgar A. Mearns on Verde Island off northeast Mindoro. It has 

 5 whorls, and measures: Height, 12.3 mm; greater diameter, 32.2 mm; 

 lesser diameter, 24.9 mm. 



Remarks. — This is a large, flat, bright-colored race, which has a con- 

 spicuous interrupted basal color band. The malleations do not extend 

 upon the last turn, on which the spiral striation is not strongly developed 



