No. 2369. NEW MOLLUSKS FROM CUBA— TORRE AND HENDERSON. 253 



OPISTHOSIPHON (OPISTHOSIPHONA) OBTURATUM SUBOBTURATUM, new subspecies. 



Plate 39, figs. 7-11. 



This subspecies differs from the typical form in that the umbilicus 

 is not wholly closed nor concealed by the expansion of the peristome 

 and in that the last whorl is shortly solute. The color is generally 

 dark and shows a tendency in some specimens to a single narrow 

 dark band. 



Type.— A female, Cat. No. 314949, U.S.N.M., was collected by Torre, 

 Henderson, and Simpson in the cave of Los Indios in the District of 

 Banao, western part of the Cubitas range, Province of Camaguey, 

 Cuba, and measures: Length, 13.9 mm.; greater diameter, 8.9 mm. ; 

 lesser diameter, 7.5 mm.; length of aperture within, 4.6 mm.; diam- 

 eter of aperture within, 3.75 mm. 



OPISTHOSIPHON (OPISTHOSIPHONA) OBTURATUM BANAOENSE, new subspecies. 



This form resembles the typical subspecies in having the umbilicus 

 wholly sealed over by the expanded peristome, or, if not actually 

 sealed and closed thereby, at least wholly covered and concealed. 

 The only persistent difference is one of size, specimens of this form 

 being uniformly smaller. As in Opisthosiphon (Opisthosiphona) 

 obturatum, shells are usually banded. The color of the tip and first 

 nepionic whorl is reddish. 



Type.— Cat. No. 314950, U.S.N.M., was collected by Torre near 

 Banao, in the western part of the Cubitas range, Camaguey Prov- 

 ince, Cuba, and measures: Length, 11.75 mm.; greater diameter, 

 8.75mm.; lesser diameter, 7.4 mm.; length of aperture within, 4.9 

 mm., diameter of aperture within, 3.4 mm. 



OPISTHOSIPHON (OPISTHOSIPHONA) APERTUM, new species. 



Plate 40, figs. 1 and 3. 



The shell is ovate-conic, rather solid, umbilicated, decollated, 

 narro vly truncated, leaving four convex whorls, the last being shortly 

 solute. The color is usually a pale straw of bright luster, but some 

 specimens are darker even to rich wine color. The lighter tinted 

 shells have a narrow reddish brown sub-peripheral band. The 

 sculpture consists of fine axial threads, more widely spaced and ele- 

 vated upon the earlier postnuclear whorls, but more crowded and 

 flatter on the last whorl. Most of the axial threads are expanded 

 into very minute white bulbs at the suture, forming an inconspicuous 

 irregular crenulation. Spiral sculpture confined to nine to ten low 

 inconspicuous cords within the umbilicus. The aperture is vertical, 

 oval, and obtusely pointed above. The double peristome has the 

 inner peritreme scarcely projecting, and the outer peritreme but 

 slightly expanded on the right, but somewhat more so on the left 

 or inner side, though not reflected over the umbilicus nor sufficiently 



