BRACHYPODELLA, S. STR. 77 



In the smooth apical whorls, the first one being somewhat 

 abnormally elevated (see Vol. XV, pi. 64, f. 15, 16, B. anti- 

 perversa), this group of species differs from the continental 

 forms, which in dentition and other respects are closely re- 

 lated. 



Key to Species. 

 I. Axis noticeably twisted; closely and finely rib-striate. 



1. Diam. 2, length 6.4 to 7.3 mm., with 7% to 9 whorls 

 remaining. Caracao. B. raveni, no. 28. 



2. Diam. 2.5, length 9 mm., with 9-9y 2 whorls remain- 

 ing; spire somewhat swollen in the middle. St. 

 "Lucia. B. tatei, no. 30. 



II. Axis straight; diam. 2.4 to 2.7 mm. 



1. Sculpture of low, rather coarse riblets; last whorl 

 hardly or not free. Barbados. B. costata, no. 29. 



2. Sculpture of much finer riblets; last whorl very 

 shortly free. Martinique; Guadeloupe. 



B. antiperversa, no. 31. 



28. B. RAVENI (' Bid.' Crosse). PL 7, figs. 40, 41, 42. 



Shell small, shortly rimate, cylindric-fusifonn, rather 

 broadly truncate, corneous with whitish riblets, thin. Sur- 

 face lusterless, closely and finely costulate, the riblets oblique, 

 narrower than the intervals. Whorls slightly convex, the last 

 swollen at the periphery, carinate beneath, concave above the 

 keel, very shortly free in front, not descending. Aperture 

 rounded, slightly angular outwardly; peristome reflexed. 

 Axis slender, encircled by a small and narrow spiral cord. 



Length 6.4, diam. 2 mm., whorls iy 2 . 



Length 7.25, diam. 2 mm., whorls 8y 2 to 9 (Crosse, types). 



Curacao (Henry Raven, J. S. Gibbons) ; Buen Ayre (E. 

 Hartert) . 



Cyl. raveni Bland MSS., CROSSE, Journ. de Conchyl., xx, 

 1872, p. 157 ; CROSSE & BLAND, J. de C., xxi, 1873, p. 40, pi. 1, 

 f. 4. PFR., Monogr., viii, p. 441. GIBBONS, Quart. Journ. of 

 Conch., i, p. 340. MARSHALL, t. c., p. 380. B. A. SMITH, 

 Proc. Malac. Soc. Lond., iii, p. 113, 115 (1898). 



A small species, more finely rib-striate than B. costata or 



