168 PROCEEDINGS OF THE NATIONAL MUSEUM Vol.89 



Bartscli collected it also at the mouth of the Rio Ojo del Toro in 

 Oriente Province. 



Bermudezsiphona, new subgenus 



In this subgenus the spiral sculpture is confined to the umbilicus. 

 (Sometimes there is an indication of it on the early postnuclear whorls.) 

 The intercostal spaces are marked by microscopic axial threads. 



Type: Opisthosiphon {Bermudezsiphona) bermudezi, new species. 



KEY TO THE SPECIES OF THE SUBGENUS BERMUDEZSIPHONA 



Umbilicus closed. 



Outer peristome erect cucuUatum 



Outer peristome not erect. 



Outer peristome suberect palmeri 



Outer peristome not suberect. 



Outer peristome horizontally expanded. 

 Outer peristome broad. 



Shell ovate greenfieldi 



Shell elongate-ovate. 



Axial ribs of last whorl strongly developed. 



Basal peristome broadly expanded, lamellosura 

 Basal peristome only moderately 



expanded plateroense 



Axial ribs of last whorl not strongly 



developed prominuluni 



Outer peristome narrow. 

 Shell ovate. 



Axial ribs very closely spaced banaoense 



Axial ribs not closely spaced obturatum 



Shell elongate-ovate obtectum 



Shell not elongate-ovate. 



Shell subcylindric insulanum 



Umbilicus open. 



Last whorl decidedly solute. 



Axial ribs sublamellar salustii 



Axial ribs not sublamellar evanidum 



Last whorl not decidedly solute. 



Last whorl subsolute subobturatum 



Last whorl not subsolute. 



Last whorl adnate to preceding turn. 



Inner lip of outer peristome strongly notched or 

 folded. 



Axial ribs distantly spaced torrei 



Axial ribs not distantly spaced. 



Shell elongate-ovate caguanense 



Shell ovate or pupoid subobtectum 



Inner lip of outer peristome not notched or folded. 



Shell elongate-ovate aguilerianum 



Shell ovate or pupoid. 



Axial ribs closely spaced detectum 



Axial ribs distantly spaced bermudezi 



Outer peristome narrow. 



Outer peristome broad andrewsi 



