BRACHYPODELLA, S. STR. 65 



In groups II and III, the initial half whorl appears some- 

 what unduly elevated, approaching the condition of the 

 Jamaican subgenera. j 



The radula in the typical group of Brachypodella is char- 

 acteristic. The central tooth has a very wide cusp (see pi. 9, 

 figs. 3, 4, B. antiperversa) , far wider than the marginal teeth 

 or than its own basal-plate. Its edge may be either straight, 

 or bilobed (as in trinitaria, pi. 9, fig. 16), the latter condition 

 perhaps being brought about by wearing of the median part 

 of the cusp, while the sides, protected by the large laterals, 

 are less worn. The inner lateral tooth on each side has the 

 basal-plate very narrow in front (above in the figures), so 

 that the small ectocone seems born on the end of a slender 

 peduncle, which is crowded inward, so that the ectocone stands 

 close to the basal-plate of the median tooth (fig. 16, etc.). 

 Finally, the two lateral teeth on each side are more or less 

 crowded together, so that in a superficial view there seems to 

 be a single row of large laterals on each side (pi. 10, fig. 17, 

 B. pallida; fig. 24, B. dominicensis) . I have examined the 

 radula of the following species: costata (pi. 9, fig. 5), collaris f 

 antiperversa (pi. 9, figs. 3, 4), raveni (pi. 9, fig. 14), trinitaria 

 (pi. 9, fig. 16), pallida (pi. 10, fig. 17), riisei, dominicensis 

 (pi. 10, fig. 24), leucopleura (pi. 9, fig. 13, an inner lateral in 

 profile), hanleyana f bourguignatiana, subtilis, morini (pi. 9, 

 figs. 9, outer, and 10, inner, laterals in profile), and spelunca 

 (pi. 9, fig. 15), so that practically the whole group is known 

 to agree in the peculiarities described above. 



Group of B. morini: southeast Mexico to Trinidad. 



Slender, long shells, usually with 18 to 25 whorls in entire 

 specimens, but usually more or less truncate. Apical 3 whorls 

 delicately costulate or striate vertically, the first whorl not 

 abnormally elevated. Axis encircled by a distinct, though 

 small, spiral lamella. 



A natural group of closely related species, differing from 

 those of the Caribees by the distinctly twisted axis and sculp- 

 tured apical whorls, by the greater number of whorls in entire 

 shells, and the somewhat longer neck. B. aequatoria, said to 



