320 PROCEEDINGS OF THE NATIONAL. MUSEUM Vol.89 



ANNULABIA (DIPLOPOMA) OBSOLETA. new species 



Plate 35, Figure 4 



Shell elongate-ovate, thin, translucent, pale yellow. Nuclear 

 whorls decollated m our specimens. Postnuclear whorls somewhat 

 inflated, well rounded, marked by distantly spaced axial riblets on the 

 early turns, which on the later whorls become quite obsolete, being 

 prominent only at the suture in the shape of slender expanded auricles. 

 The spiral sculpture appears entirely absent. Suture well constricted. 

 Periphery somewhat inflated, well rounded. Base moderately long, 

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

 by 9 spiral threads on the umbilical wall. The last whorl is solute for 

 about one-fourth of a turn, with a shghtly denticulate carina at the 

 posterior angle. Apertm-e broadly oval; peristome double, the inner 

 moderately exserted and reflected; the outer broadly expanded, 

 shghtly fluted, and marked by concentric laminae, which are a httle 

 narrower on the parietal wall than on the rest. 



The type, U.S.N.M. No. 535641, probably a male, was collected 

 by Dr. Ramsden at La Cueva, Diego Cobas, Majaguabos, Oriente 

 Province. It has 5 whorls remaining and measures: Length, 9.3 mm. ; 

 greater diameter, 5.7 mm.; lesser diameter, 4.2 mm. 



Dr. de la Torre's collection contains another specimen from the 

 same locality which is considerably larger, evidently a female. A 

 female specimen, U.S.N.M. No. 535642, collected by Dr. Ramsden 

 at Subida a La Campana por Reuter, has 4.3 whorls and measures: 

 Length, 11.4 mm.; greater diameter, 6.5 mm; lesser diameter, 5.2 mm. 



The exceeding thinness and translucence of the shell, combined 



with the obsolete sculpture, will differentiate this from the other species 



of the genus. 



JuANNULARiA, new subgenus 



Annularias with elongate-ovate shell; strong sublamellar spiral 

 cords as well as the spaces between them are crossed by numerous 

 closely crowded, fine axial threads, wliich render the spiral cords 

 finely denticulated. Peristome double. Operculum typically annu- 

 larid. 



Type: Annularia (Juannularia) perplicata (Gundlach). 



KEY TO THE SPECIES OF THE SUBGENUS JUANNULARIA 



Suture channeled perplicata 



Suture not channeled arguta 



ANNULARIA (JUANNULARIA) PERPLICATA (Gundlach) 



Plate 37, Figure 5 



1857. Cydosloma {Choanopoma) 'perplicatum Gundlach, Malakozool. Blatter, 

 vol. 4, pp. 177-178. 



