HISPANIOLAN AND BAHAMAN ANNULARIIDAE 157 



by numerous, very fine, closely spaced spiral lines. A series of scallops 

 arranged in spiral order may be present or absent on the outer portion 

 of the open umbilicus. Aperture almost circular; peristome double, the 

 outer decidedly expanded. Operculum with subcentral nucleus provided 

 with an obliquely slanting lamella. 



Type species : Choanopoma blandii Weinland = Weinlandipoma hlandii 

 (Weinland). 



KEY TO THE SPECIES OF WEINLANDIPOMA 



Lamellar axial ribs wavy. 



Outer peristome of inner lip reflected inward as a shelf gonavense 



Outer peristome of inner lip not reflected inward as a shelf. 



Outer peristome deeply excised on parietal wall excisum 



Outer peristome not deeply excised on parietal wall. 



Outer peristome broadly expanded all around strictecostatum 



Outer peristome narrower on the parietal wall. 



Axial ribs decidedly scalloped orcutti 



Axial ribs feebly scalloped blandii 



Lamellar axial ribs not wavy. 



Axial ribs numerous and closely spaced milleri 



Axial ribs fewer and more distantly spaced meridianum 



WEINLANDIPOMA GONAVENSE (Weinland) 



Shell varying from ovate to elongate-ovate, varying in color from 

 flesh color to brown, unicolor or marked by interrupted spiral bands of 

 brown, which terminate in conspicuous rays on the outer peristome. 

 Nuclear whorls 1.8, small, inflated, forming a rather sharp apex. The 

 postnuclear whorls are strongly rounded and marked by lamellar axial 

 ribs, which bear scallops arranged in regular spiral series and which 

 give to the ribs a wavy outline. Between the lamellar ribs one or more 

 finer axial threads may be present. The intercostal spaces are marked by 

 numerous, very fine, closely spaced, spiral threads separated by spaces 

 about as wide as the threads. These become apparent only under high 

 magnification. Suture strongly constricted. Base short, strongly rounded, 

 openly umbilicated, and marked by the continuation of the axial ribs and 

 on the umbilical wall by strong, almost lamellar cords. Aperture almost 

 circular ; peristome double, the inner slightly exserted and reflected ; the 

 outer broadly expanded on the outer and basal lip, less so on the inner 

 lip and slightly so on the parietal wall. The outer peristome is composed 

 of a series of lamellae which on the inner lip curl inward clawlike, that 

 is, all except the last one, which has a normal slant. Operculum with 

 central nucleus bearing a decidedly oblique, strongly elevated lamella. 

 The species is confined to the southwest coast of Haiti, the lie a Vache 

 and Gonave Island. 



I am recognizing three subspecies, which the following key and de- 

 scriptions will help to differentiate : 



