140 BULLETIN 181, UlSnTE© STATES NlATXOlNlAIj MTJSIETJM 



Adams' type, here figured, has 5 whorls and measures : Height, 13,0 

 mm. ; greater diameter, 19.4 mm. ; lesser diameter, 15.4 mm. 



Adams cites merely Jamaica, but Chitty {loc. cit.) states: "Near 

 Moore Town, Portland." He says, "This shell was originally brought 

 to me by a negro named Shelly, whom I could never, even by money 

 excite to sufficient energy to collect more. * * * Operculum still 

 wanting." 



The species has not been rediscovered, and until the operculum has 

 been found it will be impossible to place it properly. The peculiar 

 sculpture, the sloping spire, and, above all, the flattish base, differentiate 

 it from all the other known West Indian cyclophorids. 



INCERTICYCLUS PERPLEXUS. new species 

 Pl,ATE 18, FlGTTBES 19-21 



Shell small, depressed-helicoid, covered with a golden-brown perio- 

 stracum, at least the fragments left on our specimens would indicate 

 that that is the case. The nucleus consists of 1.4 small, somewhat 

 inflated, well-rounded, smooth turns. The first postnuclear whorl is 

 strongly rounded and marked by very regular, rather distantly spaced, 

 slender, well-raised axial riblets. On the succeeding turns the axial 

 riblets are more closely approximated and reduced to incremental lines. 

 In addition to these, the entire surface is marked by strong, very 

 oblique, decidedly protractively slanting heavy ridges, which are 

 separated by spaces about as wide as the ridges. These ridges at the 

 periphery join the ridges on the base, which have a decidedly opposite 

 slant, the two at their junction forming sharp arrowpoints. Base 

 broadly, openly umbilicated, inflated, well rounded, and marked by the 

 heavy rugations mentioned above. The umbilical wall bears coarse, 

 more or less vertical, riblike incremental lines. Aperture circular; 

 peristome simple, that of the outer lip thin ; the inner lip thickened. 

 Operculum unknown. 



The type, U.S.N.M. No. 535988, was collected by Orcutt at Appleton, 

 St. Elizabeth, Jamaica. It has 3.3 whorls remaining and measures: 

 Height, 7.8 mm. ; greater diameter, 14.9 mm. ; lesser diameter, 11.3 mm. 



U.S.N.M. No. 378448 contains two topotypes received from the same 

 source. These are a little smaller than the type. 



INCERTICYCLUS MARTINICENSIS (Shnttleworth) 



1857. Cyclostoma (Cyclotus) martinicense Shuttleworth, Journ. Conchyl., vol. 

 5, p. 267. 



Shell broadly umbilicated, lenticular, thin, finely striated, with dense 

 fine spiral grooves, pale olive-brown, shining; spire little elevated. 

 Apex rather obtuse; suture deep; 4-4i/^ convex, rapidly increasing 



