No. 2369. NEW HOLLUSKS FROM CVBA—TORRE AND HENDERSON. 261 



the whorls into white hollow sublamellar bulbs. The spiral sculp- 

 ture is reduced upon the outer surface of the shell to obsolete cords 

 rendered visible only upon the early postnuclear whorls by slight 

 swellings of the axial threads. On the umbilical wall are a number 

 of spiral cords. The vertical aperture is oblong-ovate, not angled 

 above; the peristome is double: the inner peritreme very slightly 

 projecting; the outer peritreme is rather widely expanded, flaring 

 forward except over the umbilical portion, where it is sharply deflected 

 backwards and partially covers the umbilicus, above which it again 

 flares forward and is adnate to the preceding whorl ; above the aper- 

 ture it is expanded backwards into a delta-shaped projection, which 

 is coarsely concentrically ribbed upon its face and terminates in a 

 thick short siphon bent back and downward into the space be- 

 tween the solute last whorl and the adjoining whorl. This siphon 

 communicates with the interior of the shell through a large pore 

 within the posterior margin of the aperture. The operculum is 

 typical of the genus. 



Type.— Cat! No. 314959, U.S.N.M., was collected by Doctor Bar- 

 bour at the Sierra de Judas in the jurisdiction of Mayajigua, Prov- 

 ince of Santa Clara, Cuba, and measures: Length, 14.4 mm.; greater 

 diameter, 8.S mm.; lesser diameter, 6.5 mm.; length of aperture 

 within, 5mm.; width of aperture within, 3.9 mm. 



This species differs from its nearest ally by its short inner peritreme, 

 its greatly expanded outer peritreme, and its umbilicus but partially 

 concealed. Its sculpture is much finer upon the last whorls, the 

 axial threads being straighter. 



OPISTHOSIPHON (OPISTHOSIPHON) DETECTUM, new species. 



Plate 42, fig. 1. 



The shell is ovate-conic, the spire decollated, leaving three and a 

 half convex whorls, the last shortly solute, openly umbilicated. The 

 color is light brown suggesting bronze, somewhat darker on the first 

 postnuclear whorl and with no color bands or spots whatever. The 

 sculpture consists of widely spaced axial lamellar riblets; these are 

 very thin and sharp and white in color, each riblet being expanded at 

 the suture above into hollow lamellar tubercles and thus crenulating 

 the deeply impressed suture. These axial riblets possess just below 

 the suture a slight thickening which represents an obsolete spiral 

 cord; on the umbilical wall are several low spiral cords. The aperture 

 is vertical, rounded ovate, but without angle above; the inner peri- 

 treme is very slightly projecting; the outer peritreme is moderately 

 expanded throughout and slightly fluted on the inner projection; 

 it is not expanded over the umbilicus, but touches the whorl above. 

 Above the aperture it projects upwards and slightly backwards and 

 merges into a sharply recurved siphon which passes down into the 

 the space behind the solute last whorl. The siphon communicates 



