32 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 95 



Strongly rounded, moderately broadly umbilicated, a little more so 

 than in Schistosomophora hydrobiopsis. The outer lip is reenforced 

 by a heavy callus a little behind the peristome. Aperture broadly 

 oval and rather broadly expanded and reflected, adnate to the pre- 

 ceding turn at the parietal vi^all. The operculum is thin, horny, and 

 has 1.5 whorls, which are excentric. In the radula the rachidian tooth 



has the formula "" . The median has 7 denticles, of which the 



2-2 



middle one is much larger than the rest. The inner marginal has 8 

 denticles, the outer 7. 



The specimen described and figured, U.S.N.M. no. 420943, a para- 

 type, received from the von Mollendorfif Collection, was collected 

 by Quadras at Surigao, Mindanao, Philippine Islands. It has 5.9 

 whorls, and measures: Height, 5.2 mm; diameter, 3.0 mm. 



This species differs from Schistosomophora hydrobiopsis in being 

 stouter and having the whorls more inflated, the axial sculpture finer 

 and closer spaced and indications of spiral sculpture stronger, and in 

 having 7 denticles in the outer marginal tooth of the radula. 



SCHISTOSOMOPHORA HYDROBIOPSIS (Rensch) 

 Plate I, fig. 7; plate 2, fig. 6; plate 3, fig. 2 



1932. Oncomclania hydrobiopsis Rensch, Philippine Journ. Sci., vol. 49, pp. 551- 



552, figs. la-c. 

 1932. Blanfordia quadrasi Tubangui, Philippine Journ. Sci., vol. 49, pp. 298-299, 



pi. 2, fig. 3, pi. 5, fig. I. 

 1932. Prososthcnia quadrasi Tubangui, Philippine Journ. Sci., vol. 49, pp. 298- 



299, 301. 

 1934. Blanfordia quadrasi Bequaert, Journ. Parasit., vol. 20, pp. 280-281. 

 1934. Oncomclania hydrobiopsis Bequaert, Journ. Parasit., vol. 20, p. 281. 

 1934. Prososthcnia quadrasi Bequaert, Journ. Parasit., vol. 20, pp. 280-281. 



Shell small, elongate-ovate, thin, light horn-colored, with the 

 nuclear whorls transparent ; a slender chestnut-brown line edges the 

 peristome. Nuclear whorls 2.0, inflated, strongly rounded, glassy, 

 appearing finely granulated under very high magnification. Post- 

 nuclear whorls moderately inflated, strongly rounded, and marked by 

 rather strong, slightly retractively curved lines of growth which al- 

 most constitute axial riblets. In addition to this there are faint indi- 

 cations of spiral sculpture — so faint that only under certain angles 

 of the light does this become apparent, chiefly about the periphery 

 and the upper portion of the base. Suture strongly constricted ; peri- 

 phery inflated, well rounded. Base short, moderately umbilicated, 

 marked by the same sculpture as the spire. The outer lip is reenforced 



