HISPANIOLAN AND BAHAMAN ANNULARIIDAE 91 



a turn. Aperture subcircular; peristome double, the outer broadly ex- 

 panded, of almost equal width, only a trifle narrower on the parietal 

 wall, forming the merest indication of an auricle at the posterior angle, 

 marked by a series of concentric lines that indicate lamellae; inner 

 peristome projecting slightly above the outer, slightly expanded and 

 slightly reflected. Operculum with weak, retractively curved riblets, 

 which vanish before reaching the outer edge of the whorls of the basal 

 chondroid plate. 



This species extends along both coasts of the southern peninsula as 

 well as on Grande Cayemite Island and lie a Vache. I am recognizing six 

 subspecies, which the following key and definitions will help to differen- 

 tiate : 



KEY TO THE SUBSPECIES OF ORCUTTIPOMA ROLLEI 



Shell cylindroconic vachecolum 



Shell elongate-ovate 



Axial ribs lamellar. 



Axial ribs very strongly scalloped fauxcapense 



Axial ribs moderately strongly scalloped blanchardi 



Axial ribs sublamellar. 



Axial ribs very strong roUei 



Axial ribs not very strong. 



Shell stout cayemitense 



Shell not stout serraticosta 



OBCITTTIPOMA BOI.L.EI VACHECOliUM, new subspecies 



Plate 14, Figure 4 



This subspecies is confined to the lie a Vache off the south coast of the 

 south peninsula where Orcutt collected numerous specimens at ten dif- 

 ferent stations. 



This race is distinguished from the rest by having the shell more 

 slender, that is, cylindroconic; the axial ribs are strong and strongly 

 scalloped. Of these scallops, six occur on the axial ribs on the last turn, 

 three on the base, and one within the umbilicus. Those on the base and 

 umbilicus are much weaker than those on the spire. 



The type (U.S.N.M. No. 504002) comes from Landefue Bay. It has 

 4.9 whorls remaining, and 41 axial ribs on the last turn, and measures : 

 Height, 7.0 mm. ; greater diameter, 3.7 mm. ; lesser diameter, 2.9 mm. 



U.S.N.M. No. 401802 contains 532 topotypes. 



U.S.N.M. No. 404919 contains 121 specimens collected by Orcutt at 

 Lancedufont Soulette, the second cliff west of Garde d'Haiti Station, lie 

 a Vache. 



U.S.N.M. No. 404934 contains 48 specimens collected by Orcutt at 

 Lancedufont on the last cliff west of Garde d'Haiti Station. 



U.S.N.M. No. 403476 contains 424 specimens collected by Orcutt at 

 Sommant Petilence, first chff west of Garde d'Haiti Station, south- 

 eastern part of the hill. 



