168 



PROF. E. YON MARTENS ON THE SHELLS 



39. Onchidium coriaceuat, Semper, he. cit. 



Dorsal tubercles small, unequal ; eye-spots in small groups. 

 Colour above brown, with very large black patches, one longi- 

 tudinal in the median line ; under surface of the mantle blackish. 

 Mantle rather rigid. 



Sullivan Island, highest " level of beach." Nicobars, Singa- 

 pore, Siam, Philippines, Moluccas, Australia. 



AMPHIBOLIDiE. 



40. Ampullarina burmana, Nevill, Journ. As. Soc. Bengal, 

 1867, pi. 2. figs. 7-10. 



Mergui, on mud-flats. Mouth of the Iraivaddi, Begu, Bombay. 



b. PECTINIBEANCHIA and SCUTIBEANCHIA. 



Columbellid^;. 



41. Columbella (Ptjsiostoma) Duclosiana, Sow., Beeve, 

 Conch. Icon. xi. pi. xv. fig. 76. 



Mergui, mud-flats, in society with Neritina crepidularia. King 

 and Elphinstone Islands. 



This is the only species of Ehachiglossate proboscidiferous 

 Gastropods ; its dull-brown colour differs remarkably from that 

 of other Columbella, and agrees more with that of the inhabitants 

 of brackish water. Malacca, Singapore. 



CERITHIIDiE. 



42. Cerithium patultjm, Sow. Thes. Conch, vol. ii. p. 871, 

 pi. 179. fig. 74 ; Beeve, Conch. Icon. xv. pi. v. fig. 33. 



Cerithium gibberosura, Bunker, Moll. d. Novara Exped. pi, 1. fig. 7. 



Eecognizable by a strong rough varix on the back of the last 

 whorl opposite to the aperture. 



Mergui, King Island Bay, littoral. Elphinstone Island Bay, 

 on trunks of mangrove-trees ; Kisscraing Island. Singapore, 

 Celebes, Moluccas, Philippines f Carolines. 



48. PoTAlCIDES (Cebithitea) obtusus, Sow., Kiener, Species 

 (I. (Jor/., Cerithium, pL fig. 2; lLombron Sf Jacf/uinot, Voy. 

 Pole Sad, Moll. pi. 2)}. fig. 3 ; Reeve, I. c. xv. Cerithidoa, pi. i. fig. 4. 



Mergui, King Island Bay, on mangroves. Nicobars ?, Salang t 

 Singapore, Celebes, Caroline Islands. 



