Alt. 



Diaiu. 



Ap. Length 



Ap. Width 



50 



31 



21 



15 mm. 



42 



27.5 



19 



13.5 



44.5 



30.5 



20.5 



15.5 



42.5 



27 



20 



13 



335 



individuals, but obsolete in others. The bands frequently tessellated with 

 cartridge buff hydrophanous spots. 



Nuclear whorl slightly depressed in most individuals, but succeeding whorls 

 rapidly descending to body whorl. Whorls 5H to 6. Body whorl slightly 

 angulate medially. Aperture quadrate, showing a broad angle at the juncture 

 of the columella and the parietal wall, and wide at its base. Peristome thin,, 

 narrow, but sharply reflected. Columella wide above and fairly straight, 

 but gradually narrowing where it shades off into the base of the aperture. 



The aperture of H. cincinniformis is more oblique than that of H. cincinni- 

 J or mis lubanensis, while the columella of the former is straight and rather 

 thick above, becoming sharply constricted below, contrasting with the almost 

 straight columella of the latter. In the general varieties of shape and size 

 H. cincinniformis and H. cincinniformis lubanensis are practically alike. 



Holotype, M. C. Z. no. 79166 

 Paratype, M. C. Z. no. 79165 



Holotype— M. C. Z. no. 79166. Paratypes:— M. C. Z. no. 79165. Pedro 

 de Mesa, collector, Lubang, P. I. 



12. Helicostyla cincinniformis tritaeniata Mllf. 



PI. 17, fig. 2. 



13. Helicostyla cincinniformis ultima, var. nov. 



PL 17, fig. 4. 



Description. — Shell, ovate-conic, moderately thin. White at nuclear whorl 

 shading off into an ivory yellow ground color on the body whorl and the 

 preceding whorl. Lower two-thirds of body whorl covered with seal brown 

 wash which in turn shades off into ivory yellow at the parietal region. This 

 wash terminates at the edge of the peristome. Seal brown band above the 

 sutures sometimes extending below the sutures, but fading out as it approaches 

 the nuclear whorl. Median line of the body whorl and margins above and 

 below the sutures often tessellated with cartridge buff hydrophanous spots. 



Nuclear whorl slightly flattened, moderately descending to the body 

 whorl. Whorls 4%. Body whorl angulated at mid-line. Aperture quadrate, 

 forming rather broad angle at the point where the columella and parietal 

 wall meet. Peristome narrow, thin, sharply reflected, tinged with seal brown 

 at the edge. Columella straight, thin, narrowing where it shades into the 

 peristome. 



Ham. A p. Length. Ap. Width, 



Holotype, M. C. Z. no. 79169 

 Paratype, M. C. Z. no. 79170 



Alt. 



Diam. 



Ap. Length 



Ap. Width 



35.5 



25 



18 



13 mm. 



43 



31 



20.5 



15 • 



42.5 



39.5 



20.5 



14 



31.5 



24 



16.5 



12 



