No. 2327. THE ANNVLARIIDAE— HENDERSON AND BARTSCH. 61 



CHONDROPOMORUS, new subgenus. 



Shell elongate-conic, marked by both axial and spiral threads, the 

 axial threads being gathered into tufts at the summits of the whorls. 



lype of the subgenus. — Cydostoma dentatum Say. 



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

 into two groups, as follows: 



The group of Cliondroimmorus deniaium: 



Cydostoma dmtatvm Say Florida-Cuba. 



Chondropoma dilaiatum (Gundlach) Pieifter Eastern Cuba. 



Cydostoma negledmn (Gundlach) Pfeiffer Eastern Cuba. 



Cydostoma delatreanum Orbigny Central Cuba. 



Cydostoma cancscens Pfeiffer East-Central Cuba. 



Cydostoma revindwni Poey Eastern Cuba, Bahamas. 



Cydostoma salkana Pfeiffer Santo Domingo. 



Cydostoma litturatum Pfeiffer Santo Domingo. 



Cydostoma (Chondropoma) hemiotiim Pfeiffer Santo Domingo. 



Cydostoma petitiana Pfeiffer Haiti. 



Cydostoma caricae Pfeiffer Santo Domingo. 



Chondropoma subreticulatum Maltzan Haiti. 



Chondropoma adulteratum. Pfeiffer Santo Domingo. 



Chondropoma bi/orme Pfeiffer Bahamas. 



Cydostoma erectum. (Gundlach) Pfeiffer Eastern Cuba. 



Chondropoma abnatiun (Gundlach) Pfeiffer Eastern Cuba. 



Chondropoma textam (Gundlach) Pfeiffer Eastern Cuba. 



Cydostoma candeanam Orbigny Eastern Cuba. 



Cydostoma crenulata Ferussac Guadeloupe. 



Cydostoma {Chondropoma) newtoni Sliattleworth Porto Rico. 



Cistula rmei Pfeiffer Porto Rico. 



Chondropoma rawsoni Pfeiffer Bahamas. 



Chondropoma tvatlingense Dall Bahamas. 



The group of Cliondropomorus saniacruzense: 



Chondropoma saniacruzense Pfeiffer St. Croix. 



Cydostoma basicarinattim Pfeiffer St. Croix. 



Cydostoma newcombianam C. B. Adums St. Thomas. 



Chondropoma tortolense Pfeiffer Tortola. 



Adamsidia diordata (Gundlach) Pfeiffer Eastern Cuba. 



Subgenus CHONDROPOMA Pfeiffer. 

 1847. Chondropoma Pfeiffer, Zeitschr. Malak., vol. 6, p. 109. 



Shell ranging in form from ovate-conic to elongate-conic. The 

 axial sculpture consists of ribs or riblets which vary considerably in 

 strength in the different species. The riblets are never gathered into 

 tufts at the summit. The spiral sculpture is also quite variable, 

 but regardless of its strength it is found upon all parts of the spire 

 and base. The peristome may be simple or expanded. No breathing 

 device is present. Operculum typically Chondropomoid. 



Tiipc of the subgenus.— Cydostoma semilahre Lamarck. 



