78 



Figure. 



Chama lazarus. PL 30. Tig. 174. Shell of a young specimen, rather 

 highly coloured. 



Genus 2. ETHERIA, Lamarck. 



Animal; oblong, thick, with the mantle lobes freely open ; labial 



palps large, no foot. 

 Shell ; irregular, affixed, of a glaucous green colour, somewhat 



pearly within, the nacre being mostly blistered ; teeth obsolete. 



The fresh-water Oysters of the Nile, as the traveller Bruce called them, 

 collected abundantly by another eminent traveller in the same locality, M. 

 Cailliaud, differ from the rest of the freshwater bivalves in their Chama- 

 like character of adhering to foreign bodies, and even attaching themselves 

 one upon another in masses. M. Cailliaud collected them in Upper Nubia 

 as high up as the cataracts of Robatas, where he found that the animal 

 was eaten by the natives as a common article of food, and the shells col- 

 lected by them for decorating their tombs. Lately the genus has been 

 found in the river Amazon. The shell is of a peculiar livid, glaucous 

 green colour, the interior being lined with a nacre, which is in most spe- 

 cimens raised into blisters, and the outer surface is sometimes rudely tubu- 

 larly scaled. 



