60 PROCEEDINGS OF TEE NATIONAL MUSEUM. vol. 58. 



CHONDROPOMIUM, new subgenus. 



Shell varying in shape from ovate to elongate-conic, marked by 

 axial ribs on spire and base. Spiral sculpture absent except on the 

 umbilical wall, where spiral cords are present. Operculum typically 

 Chondropomoid . 



Type of the subgenus. — Chondrojmm-a weinlandi Pfeiffer. 



The following species are now referred to this subgenus. They fall 

 easily into three groups as follows: 



The group of Chondroporaium weinlandi: 



Cydostoma weinlandi Pfeiffer Haiti. 



Chondropoma weinlandi superba Henderson and Simpson Haiti. 



Cydostoma {Chondropoma) eusaratm Pfeiffer Santo Domingo 



Cydostoma magnifica (Salle) Pfeiffer Santo Domingo 



Cydostoma ( Tudora) nobilis Pfeiffer Santo Domiugo. 



The group of Chondropomiurn amhigua: 



Cydostoma amhigua Lamarck Haiti. 



Cydostoma qutierezi (Gundlaoh) Pfeiffer Eastern Cuba. 



Cydostoma andrewsae Ancej' Utilla. 



The group of Cfiondropomiura lindeniana: 



Chondropoma lindeniana Weinland Haiti. 



Cydostoma loueana Pfeiffer Santo Domingo. 



Cydostoma papyracea Adams Jamaica. 



Cydostoma ruhicundum. Morelet Guatemala. 



Cydostoma plicatulum Pfeiffer Venezuela. 



CHONDROPOMETES, new subgenus. 



Shell of turbinate form, openl}' umbilicated, marked by axial and 

 spiral threads. Operculum typically chondroi)omoid with the 

 nucleus sub central. 



Type of the suhgrnus. — Cliondropoma vignalensls (Gundlach) 

 Pfeiffer. 



The following species are referred to this subgenus : 



Chondropom/i vignalensis (Wright) Pfeiffer Western Cuba. 



Cydostoma latilabre Orbigny Western Cuba. 



CHONDROPOMARTES, new subgenus. 



Shell of ovate-conic form, the intersections of the axial ribs and 

 spiral threads forming sharj) cusps. Operculum ty])ically Chon- 

 dropomoid. 



Type of tltr suhgc.nus. — Cliondropoma pnsasiaha (Ciundlach) 

 Pfeiffer. 



The following species are now referred to this su])genus: 



Chondropoma presasiana (Gundlach) Pfeiffer >[atauza8, ('uba. 



Chondropoma scobina (Gundlach) Pfeiffer \\'e8tern ( Hiba. 



Chondropoma discolorans i^ Wright) PfeilTer Western Cuba. 



Cydostoma dunkeri Arango Eastern Cuba. 



Chondropoma ru/opidnm (Gundlach ~i Pfeiffer Eastern Cii ba. 



