517 



33. Neritina obtusa (pi. cxi. f. 72, 73), Benson. 



N. testa transverse ovali, leviter striata, epidermide subviridi 

 mduta; spira depressa, anfractibus duobus ; apertura, magna, sub- 

 cinerea ; labio externo interne crassiusculo ; labio interne- com- 

 planato, recedente, margine sinistro oblique acuto, margine dextro 

 in medio subarcuato, subcrenulato. Opcrculo cinereo. 



Transversely oval, sHghtly striated, covered with a dingy olive 

 epidermis. The spire is rather flat, consisting of two whorls ; the 

 body-whorl and aperture is very large. The left margin of the 

 columellar lip presents a sharp keel half-way up ; the right margin 

 slightly arcuated and crenulated in the centre. The inner edge 

 of the outer hp is thickened inside. 



Banks of the Ganges, Calcutta. 



34. Neritina Panayana (pi. cxv. f. 191). 



N. testa N. obtusa simili, sed lineis griseis minute angidatis 

 picta ; labio externo magis expanso ; labio interno concavo, mar- 

 gine lsevigato. 



Differing from N. obtusa (Sp. 33) in the outer lip being more 

 spread at the upper part, and in the columella being smooth at 

 the edge and rather hollow. The outer surface is covered with 

 zigzag lines. 



River Dingle, Island of Panay ; on small stones. Cuming. 



35. Neritina dubia (pi. cxi. f. 81-88), Chemn. Conch. 

 5. pi. 193. f. 2019, 2020. N. reticulata, QLuoy et Gurnard. N. 

 zebra, Chemn. t. ix. p. 69. pi. 124. f. 1380. N. zebroides, Lesson. 

 N. Philippinarum, Sowerby's Conch. 111. N. fasciata, Lamarck, 

 Sowerby, Conch. 111. f. 35. N. bella, Busch, Phil. Abbild. t. 1. f. 8. 



N. testa transverse subovali, subtenui, fusca vel pallide fulva, 

 fasciis et maculis nigris varie picta ; spira rotundata, anfractibus 

 tribus ; apertura interne ad extremitates subcarinata ; labio externo 

 intus incrassato ; labio interno complanato, kevi, plerumque fusco. 

 Opcrculo griseo. 



Rather oval transversely, rather thin, brown, with various black 

 markings ; spire rounded, with three whorls ; aperture with a 

 small raised edge within, at each extremity ; and the inside of the 

 outer lip with a slight thickening. The inner lip is flat and 

 smooth. 



River Pisag, Pay of Manilla ; adhering to the piles of wharfs. 

 Cuming. 



3 x 



