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SPECIES LIII. Amblema olivaria~-(Unio 

 olivaria.) 



Shell thick, somewhat ventricose, oval, ellipti- 

 cal ; apices scarcely prominent, almost superior ; 

 epidermis wrinkled, olive-coloured ; nacre white, 

 iridescent ; lamellar tooth straight ; breadth f 

 diam. axis ^ of the length. 



Var. 1. dilatata with base dilated su- 

 periorly. 

 Var. 2. fasciolaris with radiated bands, 



brown. 



Found in the Kentucky ; length from two to 

 three inches ; this species is intermediate be- 

 tween this genus and the preceding genus. 

 Fossule visible ; cardinal tooth slightly wrinkled ; 

 lamellar tooth thick ; ligament of a gold colour. 



SPECIES LIV. Amblema rubra (Unio rubra.) 



Shell thick, ventricose, somewhat elliptical ; 

 apices scarcely prominent, with a slight oblique 

 or broad sinus ; furrow posterior ; axis almost 

 lateral ; epidermis wrinkled, blackish ; nacre 

 purple-red. Length -f diam. -| axis | of the 

 breadth. 



Var. 1. lineata reddish brown, streaked 

 with brown lines. 



