200 BULLETIN 192, UNITED STATES NATIONAL MUSEUM 



tion with the axial riblets nodulose. The spaces enclosed between the 

 ribs and spiral threads are squarish pits. Suture well constricted. Pe- 

 riphery slightly, obsoletely angulated. Base short, well rounded, nar- 

 rowly umbilicated, marked by the continuations of the axial riblets and 

 spiral threads, the latter becoming a little intensified toward the umbilicus 

 and a little more distantly spaced, those within the umbilical wall a little 

 lighter than those immediately outside it. Aperture oval ; peristome 

 double, the outer rather broadly expanded all around and reflected, 

 forming a rather conspicuous auricle at the posterior angle, and scalloped 

 on the columellar and basal wall; inner lip slightly expanded and pro- 

 jecting materially above the outer with a strong demarcation between 

 the two all around. Operculum paucispiral, submarginal, the outer sur- 

 face covered with a fine, thin, granular calcareous deposit. 



The type (U.S.N.M. No. 355076) was collected by Barton Bean and 

 J. H. Riley at Nassau, New Providence, Bahamas. It has a little over 5 

 whorls and measures: Length, 17.0 mm.; greater diameter, 8.2 mm.; 

 lesser diameter, 6.8 mm. 



U.S.N.M. No. 173184 contains 3 topotypes from the same source. 



U.S.N.M. No. 355077 contains i specimen from the Gill Collection. 



U.S.N.M. No. 366199 contains 11 specimens collected by C. C. Allen 

 at South Beach, Nassau. 



U.S.N.M. No. 467099 contains 484 specimens collected by C. C. Allen 

 at Nassau. 



U.S.N.M. No. 180675 contains 8 specimens collected by Owen Bryant 

 at Grantstown Road, Nassau, New Providence. 



U.S.N.M. No. 466013 contains i specimen collected 3 miles north of 

 the bluff in the interior of the island, Nassau, New Providence. 



U.S.N.M. No. 466024 contains 62 specimens collected at Nassau, 

 New Providence. 



U.S.N.M, No. 269212 contains 5 specimens collected by Bartsch on 

 the south shore of New Providence. 



U.S.N.M, No. 467127 contains 6 specimens collected by C. C. Allen 

 at Spanish Wells, Eleuthera. 



U.S.N.M. No. 467154 contains 3 specimens collected by C. C. Allen 

 on the sea cliffs near Corry Sound, New Providence, 



Clench in the Bulletin of the Museum of Comparative Zoology, vol. 80, 

 No. 14, p. 516, 1938, mentions the following localities on Cat Island for 

 Chondropoma' canescens Pf eiff er : "Arthurs Town ; i mi. S. E. ; 3 mi. N. 

 W. ; and 4 mi, E. of Arthurs Town; Orange Creek; ^ mi, and 2>^ 

 mi, N. E, of Orange Creek; Winding Bay; Bain Town; 3 mi. N. W. of 

 Port Howe." These may represent this subspecies. 



This offers a fine field for speculation to account for this interrupted 

 distribution. If carried by human agency, it must have been sufficiently 

 long ago to enable the New Providence forms to become subspecifically 



