CUBAN SUBFAMILY CHONDROPOMINAE TORRE AND BARTSCH 269 



The type, U.S.N.M. no. 468737, comes from Los Cayitos la Catalina 

 north of San Diego Banos. It has 5 whorls remaining and measures : 

 Length, 16.2 nnn; greater diameter, 11.7 mm; lesser diameter, 7.2 mm. 



Genus CHONDROTHYRETES Henderson and Bartsch 



1920. Chondrothyra {Chondrotliyretca) Henderson and Bartsch, Proc. U. S. 

 Nat. Mus., vol. 58, p. 64. 



Shell varying from ovate-conic to ovate-turreted, marked with axial 

 and spiral threads. Aperture varying from ovate to subcircular; 

 peristome double, the outer usually broadly expanded and reflected, 

 always deeply cut on the inner lip, with the part posterior to the cut 

 reflected over the umbilicus, which is completely or almost com- 

 pletely closed ; inner peristome short, reflected and adnate to the outer. 

 A breathing pore is present, wliich may open directly to the exterior 

 or through a connecting channel communicating with the exterior by 

 way of the hollow truncated axis. Operculum paucispiral with ex- 

 centric nucleus covered to a varying degree with a deposit of fine 

 calcareous granules. 



Type: Chondrothyretes shuttleioorthi (Pfeiffer). 



The main distribution of the members of this genus falls into Pinar 

 del Rio Province; a few species, however, extend eastward into 

 Havana Province. 



KEY TO THE SPECIES OF GENUS CHONDROTHYRETES 



Shells of medium size, thin. 



Outer peristome of inner lip, above cut, pressed into umbilicus impressa 



Outer peristome of inner lip, above cut, not pressed into 



umbilicus delectabilis 



Shell large and heavy. 



Spiral sculpture decidedly stronger than axial. 



Hydrophanous axial streaks present aflSnis 



Hydrophanous axial streaks absent. 



Axial sculpture of last whorl quite strong gundlachi 



A:xia] sculpture of last whorl feeble parilis 



Spiral sculpture not decidedly stronger than axial. 



Junctions of axial rlblets and spiral threads forming prom- 

 inent nodules. 



Outer lip conspicuously rayed tenebrata 



Outer lip not conspicuously rayed reticulata 



Junctions of axial riblets and spiral threads not forming 

 prominent nodules. 



Axial and spiral sculpture moderately strong. 

 Outer peristome thin, broadly expanded. 



Shell ponderous barbouri 



Shell not ponderous shuttleworthl 



Outer peristome thickened, not broadly expanded-- incrassata 

 Axial and spiral sculpture obsolete cerina 



