26 ART. 2. S. TOKUNAGA. 



Living : Tokyo Bay, Nagasaki, Ise, Bonin Is., China, 

 Hong-kong, Pliilippines, Shingapore, Borneo, Australia, Mergui 

 Is. and India. 



66. POTAMIDES CKR. INCISUS Hombr. and Jacq. 



PL I. Fitr. 53. 

 Tryon, Man. Conch., IX., p. 160. 



Tabata (frequent). 



Living P. incisus Hombr. and Jacq. was collected in the 

 Philippines. 



RISSOID/E. 



67. RIÎSSOA (FENELLA) cfr. CERITHINA Phil. 



PI. I. Fig. 54. 



Tryon> Man. Conch., IX., p. 395.— Ann. Mag. Nat. Hist., VI. 1860, 



p. 421. 

 Synonym: — F. reticulata A. Ad. — F. scabra A. Ad. 



Tabata (frequent). 



Living specimens of E. cerithina Phil, were collected in 

 Japan, Red Sea, Persian Gulf and Rodriguez Is. (in Indian Ocean). 



68. RISSOA SEPTENTRIONALIS Tok. 

 PL I. Fig. 55. 



Shell turreted ; whorls seven, granulate at the intersections 

 of the longitudinal and spiral ribs as in the preceding species, 

 but the transverse lirse are not interrupted even upon the longi- 

 tudinal costse ; both ribs are also narrower than in the preced- 

 ing form and retain almost equal width throughout the whole 

 spire. Height and breadth 4'""' and 1.5'""'; or .S.S""™ and 1.5'"". 



Tabata (frequent). 



