1887.] NATURAL 8CIENCE8 OF PHILADELPHIA. 149* 



tura circularis ; perist. simplex vix incrassatum. Operculum soli- 

 duni extus perconcavum, marginibus anfractuum promiuentibus. 

 Lat. 0.13, alt. 16 poll." 



Genus OMPHALOTROPIS, Pfeiffer. 



0. conidea, Mousson. 



Omphalotropis conoidea, Mousson, Jour, de Conch., 1865, p. 182. 

 Pease. Jour, de Conch., 1869, p. 146; Proc. Zool. Soc, 1871, p. 

 476. Paetel, Cat. Conch., p. 124. Schmeltz, Cat. Mus. Godeff., v, p. 

 101. 



Realia ( Omphalotropis) conoidea, Mousson, Jour, de Conch., 1869, 

 p. 353 (et var. angulosa) ; 1871, p. 27. Pfeiffer, Mon. Pneum., iv, 

 p. 222. 



I am not acquainted with this species, which was found at Upolu 

 by Dr. Graffe, and the variety at Savaii. He found it also at 

 Wallis Island. 



An ovate conical species, 7 mill, long, with 6i rather flattened 

 whorls, the last one large, ovately-rounded, perforated, and the per- 

 foration margined by a filiform keel. Moussson says "epidermide 

 subdedituta, punctis et lineis fiilguratis mepe reticularis malleata." 

 In his remarks (Jour, de Conch., 1869, p. 146) he says "Les jeuues 

 individus, d'un rouge grisatre et peu fulgures, sont, en effet, parfai- 

 tement lisses ; mais bientot on decouvre des points d'une coloration 

 blanchatre et mate, qui interrompent les parties polies et se dis- 

 posent en lignes anguleuses, qui finissent par dominer a I'age ou 

 r 6piderme est entirement detruit." 



His variety angulata has the last whorl angular. 



0. bilirata, Mousson. 



Omphalotropis bilirata, Mousson, Jour, de Conch., 1865, p. 184, 

 pi. 14, fig. 13. Pease, Jour, de Conch., 1869, p. 146; Proc. Zool. 

 Soc, 1871, p. 476. 



Realia {Omphalotropis) bilirata, Mousson, Jour, de Conch., 1869, 

 p. 146 (var. elongata); 1871, p. 29. Pfeifier, Mon. Pneum., iv, p. 

 218. 



More rare than the preceding species and inhabits Upolu and 

 Savaii, as well as Wallis Island in the Tonga group. 



A perforated, elongate-conical, pale corneous species with an in- 

 cised sutural line which is margined above with a filiform keel. 

 Whorls 6, flattened, the last one angulated and bicarinated with a 

 periphery and basal thread-like keel. Length 51 mill. 



