360 PROCEEDINGS OF THE NATIONAL MUSEUM Vol.89 



LUGARENIA, new subgenus 



Shell varying from broadly elongate-conic to turbinate in outline. 

 Axial ribs present on spire and base. The spiral sculpture may be 

 confined to the umbilicus or it may extend over the entire shell. 

 Base openly umbilicated. Peristome double. Operculum with a 

 broadly expanded lamella, which is reflected outward to parallel the 

 chondroid plate, not marked by fine, retractively curved threads; the 

 lamellae of succeeding turns do not extend to the edge of the turns, 

 but they leave a band of the basal plate exposed. 



Type: Annularia (Lugarenia) najazaensis, new species. 



KEY TO THE SPECIES OF THE SUBGENUS LUGARENIA 



Junctions of axial ribs and spiral threads strongly nodulose eurystoma 



Junctions of axial ribs and spiral threads weakly nodulose. 

 Nodules obsolete on last whorl. 



Shell turbinate biayensis 



Shell elongate-ovate najazaensis 



Nodules not obsolete on last whorl. 



Last whorl adnate lirata 



Last whorl solute sifontesi 



ANNULARIA (LUGARENIA) EURYSTOMA, new species 



Shell turbinate, pale yellow, with interrupted spiral bands of brown 

 on spire and base. The elements composing these bands are also 

 arranged in axial series. There is a dark sutural band on the nuclear 

 turns. Nuclear whorls 2, small, well rounded, microscopically granu- 

 lose. Postnuclear whorls decidedly inflated, strongly rounded, 

 marked by slender, retractively curved axial threads, which are about 

 one-fourth as wide as the spaces that separate them, and by spiral 

 threads a little stronger than the axial, which render the axial riblets 

 granulose at their junctions. At the summit of the whorl the axial 

 riblets project slightly into the suture and appear finely spinu- 

 lose. Suture narrowly channeled. Periphery inflated, well rounded. 

 Base short, well rounded, openly umbilicated, and marked by the 

 continuation of the axial riblets and spiral threads, the junctions of 

 which lilcewise form granulations. On the umbilical wall the spiral 

 threads become emphasized and the axial riblets reduced, but here 

 also the junction forms slender nodulations, the long axis of which 

 coincides with the axial sculpture. Aperture broadly oval; peristome 

 double, the inner either moderately exserted or reflected and ap- 

 pressed to the outer. Operculum typically lugarenid. 



This species comes from southern Camagiiey Province. We are 

 recognizing two subspecies, which the following key will help to 

 differentiate: 



