150 PROCEEDINGS OF THE ACADEMY OF [1887. 



0. bifilaris, Mousson. 



Omphalotropis bijilaris, Mousson, Jour, de Conch., 1865, p. 183. 

 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. 



Realm {Omphalotropis) bifilaris, Mousson, Jour, de Conch., 1869, 

 p. 353 (var. angusta); 1871, p. 29. PfeifFer, ]Mon. Pneum., iv, p. 

 232. 



Not infrequent at Upolu and Tutuila ; found also at the Tonga 

 group. Mousson's variety angusta which inhabits the Viti Islands 

 is probably a distinct species. 



The type is a perforated, conical shell, 6| mill, long, with a fuga- 

 ceous fuscous epidermis and rounded whorls, the last one with a 

 periphery and basal filiform keel. 



HELICINA.. Lamarck. 

 H. fulgora, (Jould. 



Helicina fidgora, Gould, Proc. Bost. Soc. Nat. Hist., 1847, p. 201; 

 Exp. Exp. Shells; p. 95, fig. 106. Pfeiffer, Mon. Pneum., i. p. 401. 

 Gray, Cat. Phan., p. 293. H. and A. Adams, Gen. Moll, ii, p. 302 ; 

 Mousson, Jour, de Conch., 1865, p. 178 ; 1869, p. 356 ; 1870, p. 198 

 (var. expansa); 1871, p. 25 (var. diminuta). Pease, Proc. Zool. Soc, 

 1871, p. 476. Paetel, Cat. Conch., p. 125. Schmeltz, Cat. Mus. 

 Godeff.. V, p. 98 (var. delicatula). 



Helicina delicatula, "Mss." Paetel, Cat. Conch., p. 125. 



Abundant beneath decaying vegetation and is diffused throughout 

 the grou}). The variety delicatula is common at Samoa, and 

 Mousson's diminuta is widely spread over the Tonga group. Vari- 

 ety expansa inhabits Kanathia, one of the Viti Islands. 



This variable species may be recognized by its conoid form, thin 

 texture, oblique striation, yellowish horn-color and radiating angu- 

 lar or flexuous rufous strigations. Sometimes the stripes are inter- 

 rupted so as to form a series of spots along the sutural line and on 

 the acutely carinated j^eriphery. The peristome is slightly expanded 

 and forms an angle at its junction with the short columella. 



Diam. 4 to 9 mill. 



H. plicatilis, Mousson. 



Helicina plicatilis, Mousson, Jour, de Conch., 1865, p. 178; 1869, 

 p. 358. Pease, Proc. Zool. Soc, 1871, p. 476. Paetel, Cat. Conch., 

 p. 126. Brazier, Proc. Zool. Soc, 1871, p. 322. Schmeltz, Cat. Mus. 

 Godeff., V, p. 98. Pfeiffer, Mon. Reunion, iv, p. 251. 



