THE NAUTILUS. 

 NEW CUBAN SPECIES OF UROCOPTID.E. 



BY CHARLES T. RAMSDEN. 



UKOCOPTIS (!DIOSTEMMA) PILSBRYANA n. sp. PI. I, figs. 3, 4. 



The shell is white, truncate, retaining 14 or 15 whorls in the adult 

 stage, the truncation closed by a very convex plug ; upper third 

 tapering, the remainder cylindrical. Whorls flat, the last two or 

 three convex ; base with a very weak revolving cord or none. The. 

 surface is dull, with sculpture of low axial ribs, which are narrow 

 and weak in the middle of each whorl, enlarged at both ends, which 

 abut against ribs above and below, the ribs being, as it were, con- 

 tinuous from whorl to whorl. In the upper part of the shell, some 

 of the ribs are hollow, as in U. uncata. Where unworn, the surface 

 between ribs is finely, sharply striate axially. The last whorl is 

 shortly free in front, and near the aperture it is dilated peripherally 

 and flattened above and below. The aperture is small, shortly 

 fusiform, the narrower part peripheral in position. The peristome 

 is expanded at the outer part, elsewhere reflected. Internal axis is 

 simple and slender in the first three whorls, then a spiral lamella 

 bearing a few projections arises, soon followed by corresponding 

 hooks from below, forming a stage of about two whorls where there 

 are pairs of converging hooks. This is followed by a stage in which 

 there is a broad, smooth superior lamella, and strong hooks arising 

 from the basal partition at intervals of about half a whorl (fig. 4). 

 Finally, in the last two whorls the hooks disappear and the spiral 

 lamella becomes low and finally disappears. 



Length 15.5, greatest diameter 3.8 mm. 



Length 16.5, greatest diameter 3.6 mm. 



Locality, " La Hembrita," Monte Toro, Guantanamo. 



This remarkable species closely resembles U. uncata externally, 

 but differs widely from that, and from all other known species, by 

 having a smooth spiral lamella in the whorls of the cylindrical part 

 of the shell. The peculiar axial armature of U. uncata and other 

 species of the subgenus Idiostemma has been figured by Pilsbry in 

 his monograph of Urocoptidf. 



BRACHYPODELLA (GYRAXIS) TORREANA, n. sp. PI. I, fig. 1. 

 The shell is extremely slender, retaining the apex perfect (two 



