502 unioninjE. 



but furnished with a lamina; ligament external, linear. 

 Pallial impression simple. 



Syn. Anodon, Oken. Limnsea, Limnceoderma, Poli. 

 Strophitus, Lastena, Limella, Rqfin. Hemiodon, Swains. 

 Anodontina, Schliit. Craspedodonta, Kiist. Pseudodon, 

 Gould. Glochidium (fry), Ratlike. 



Ex. A. cygnea, Linnceus, pi. 118, fig. 1. Shell, A. 

 cygnea, fig. 1, a s 1, b. 



Two undoubted species of Anodonta are found in the 

 fresh waters of Europe, besides numerous disputed species ; 

 a few only are African in their geographical range ; nine or 

 ten are inhabitants of the rivers of Asia ; one only is from 

 New Holland; while the remainder, in nearly equal pro- 

 portions, are from the rivers and lakes of North and South 

 America. 



Species of Anodonta. 



argentea, Lea. fragilis, Lam. 



Arkansensis, Lea. Giullaini, Recluz. 



atrovirens, Phil. gibbosa, Say. 



cognata, Gould. gigantea, Lea. 



cornea, Phil. glauca, Valenc. 



Couperiana, Lea. globosa, Lea. 



crepera, Lea. grandis, Say. 



Cumingii, Lea. Harpethensis, Lea. 



cygnea, Linn. Housatonica, Linsl. 



decora, Lea. imbecilis, Say. 



denigrata, Lea. implicata, Say. 



Dupuyi, Ray and Dronet. limnoica, D'Orb. 



edentula, Say. Linnaeana, Lea. 



feminalis, Gould. Middendorffii, Siem. 



ferruginea, Lea. Milled, Ray and Drouet. 



Ferussaciana, Lea. Mortoniana, Lea. 



fluviatilis, Lea. Nicaraguas, Phil. 



Footiana, Lea. oblita, Lea. 



