388 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



light hydrophanous cuticle ornamented by spiral lines at irregular 

 distances from one another, these in turn being cut across by rather 

 faint axial lines. As already mentioned, there is a subperipheral 

 band of hydrophanous cuticle. Peristome blackish brown; columella 

 white; aperture white; whorls 4, only slightly convex, body whorl 

 keeled; spire rather flat; peristome narrow, rounded, slightly reflected, 

 slightly recurved; columella broad, flat, and rather straight, slanting 

 at 111° angle from the basal lip inward toward the parietal wall; 

 parietal callus thin, aperture dome-shaped; suture very slightly im- 

 pressed. Sculpture consisting of closely crowded axial striae, cut 

 across by spiral lines, which are especially common below the periph- 

 ery of the body whorl." 



Holotype (Mus. Comp. Zool. no. 81353) collected at Binuangan, 

 Paluan, Mindoro, by Pedro de Mesa. It measures: Altitude, 33.5 

 mm; diameter, 39.5 mm; aperture height, 17.5 mm; aperture width, 

 16.5 mm. 



"This species is readily distinguishable from H. melanochila by it& 

 keel and its higher spire. The stronger development of spiral lines is 

 another difference. Its lighter color, especially on the spire, and 

 scantier hydrophanous cuticle are other distinguishing characteristics. 

 It also has a stronger columella. It is unique among the known 

 Helicostylae of the section Cahcochlea which occur in Mindoro in 

 possessing a definite keel. The species is probably rare; only one 

 specimen is known." 



COCHLOSTYLA (CALOCOCHLEA) ROISSYANA BARTSCHI (Clench MS.) Bartsch 



Plate 95, Figures 10-12 



1932. Cochlostyla {Cahcochlea) roissyana bartschi Bartsch, Journ. Washington 



Acad. Sci., vol. 22, p. 335. 



1933. Helicostyla (Calocochlea) roissyana bartschi Clench and Archer, Papers 



Michigan Acad. Sci., Arts, Letters, vol. 17, p. 541, pi. 17, fig. 2. 



Shell subglobular; the nuclear and early postnuclear whorls are 

 flesh-color, gradually changing to brown. There is a narrow dark 

 zone at the summit and another showing immediately posterior to the 

 periphery. The periphery is pale buff, while the base is dark brown, 

 with an obscure lighter median zone. The interior of the aperture 

 and columella are bluish white, while the outer lip is dark. The 

 entire shell is covered by a pale gray periostracum, which shows vari- 

 ous hydrophanous spiral bands both on spire and base. 



The 20 specimens of this race in our collection, collected by Pedro 

 de Mesa at Anduyanan, Paluan, Mindoro, are so uniform, both in 

 general form and coloration, that I do not hesitate to consider this a 

 good race. They yield the following measurements: 



