CYCLOPHORUS. 279 



Shell conical or depressed, last whorl rounded, without 

 any groove or ridge round the front of the axis. 



Genus CYCLOPHORUS, Montfort. 



Operculum orbicular, horny, thin, more or less concave 

 externally, with numerous narrow whorls, and. a central 

 nucleus. 



Shell globosely turbinated, depressed or discoidal, usually 

 widely umbilicated ; aperture circular ; peristome continuous, 

 straight or expanded. 



Syn. Annularia, Solium. Cyclophora, Swains. Cy- 

 clohelix, March. 



Ex. C. tigrinus, Sowerly, pi. 85, fig. 5. Operculum, 

 C. tigrinus, fig. 5, a, 5, b. Shell, C. involvulus, Midler, 

 fig. 5, c. 



The greater number of this group are inhabitants of the 

 continent of India, the East- Indian Islands, Ceylon, and the 

 Philippines ; a few are from Madagascar ; a section with the 

 peristome straight is from the Pacific Islands; and another 

 section is from South America. 



Sjiecies of Cyclojrfwrm. 



alternans, Pfeiff. Bairdi, Pfeiff. 



altivagus, Bens. Bensoni, Pfeiff. 



Amboinensis, Pfeiff. Birmanus, Pfeiff. 



amoenus, Pfeiff. Borneeusis, Metcalfe. 



Apiae, Recluz. Bourcieri, Pfeiff. 



appendicular, Pfeiff. canaliferus, Sow. 



annulatus, Trosch. Cantori, Bens. 



aquila, Sow. Cayermensis, Shuttl. 



atramentarius, Sow. Ceylanicus, Pfeiff. 



Aurora, Bens. Charpentieri, Mouss. 



