24 

 UNIO RADIATUS. 



Plate X. Fig. 2. 

 DESCRIPTION. 



Shell oblong-ovate, thin, slightly compressed on 

 the anterior side; surface with fine wrinkled lines 

 and distinct furrows; olive, with numerous green rays, 

 varying in size; anterior side short and narrowed; 

 margin abruptly rounded; posterior side dilated; liga- 

 ment margin elevated, slightly curved; anterior basal 

 margin slightly contracted; umbonial slope undefined; 

 posterior extremity subtruncated; within yellowish or 

 salmon coloured, and thickened anteriorly; bluish and 

 highly iridescent posteriorly. 



SYNONYMES. 



U. radiata, Lam. An. sans vert. vol. vi. p. 73. 



Barnes. Silliman's Journ. vol. vi. p. 265. 



Mya radiata, Spengl. Gmel. 



U. virginiana, Lam. An. sans. vert. vol. vi. p. 79. 



U. oblongata, Wood. Suppl. Index. Test. 



Cab. A. N. S.No. 1116. 



OBSERVATIONS. 



A common species in the tide waters of the middle 

 states, and very abundant in those of Virginia, but it 

 has not been found in any of the tributaries of the 

 Mississippi, except the Ouisconsin river, where, 

 according to Mr. Barnes, it was obtained by Mr. 

 Schoolcraft. This naturalist remarks that it inhabits 

 Saratoga lake. 



