OF THE FAMILY OF NAIADES. 125 



U. virginiana. This, doubtless, is the radial us described 



by Barnes. Habitat Virginia. 



U. luteola is a variety of Say's cariosus. Habitat Susque- 

 hanna and Mohawk. 



l r . marginalia. I have specimens of this species from 

 Bengal. It is well characterised, although it does not always 

 possess the marginal character as described by Lamarck and 

 represented in the Ency. Meth. pi. 247. 



U. ongusta. This 1 believe to be a variety of pictorum. 

 The figure referred to in Lister is certainly a pictorum. and 

 i> generally quoted as such. Habitat unknown. 



( '. manea. This may be a distinct species, but I strongly 

 suspect it to be only a variety of pictorum. Habitat Bour- 

 gogne. 



U. cariosa is the cariosus of Say. 



U. spuria. I cannot identify this species with any of ours. 

 Habitat 



U. australis. This, like the above, is not identified. Ha- 

 bitat New Holland. 



{'. anodontma. Habitat Virginia. We have no Unio of 

 this description in our waters. It is probably Anodonta un- 

 (liiln/ii of Say. which has sometimes small elevations some- 

 what similar to teeth*. 



I '. suborbiculata. I cannot identify thisspecii 



In passing criticisms upon the species of the genus Unio of 

 thi> great naturalist, I do no! in the least wish to detract from 

 his great and merited fame. My object is expressly to en- 

 deavour to facilitate the study of Ibis interesting genus, and 

 to remove, as far as I have it in my power, the confusion 

 which has crept into it. My observations 1 wish to pa-> 

 only For what they may prove to be worth. 



* Since v. riiinL' the above, I observe that Sowcrhv on the Lamarckian !Va "■'- 

 (Zoolog. Journ. Vi'l. I. p. 64.) givea Ibe u J0j/udon rugotut" of Bwainai n 

 the synonyme of U. anodoniina. It is well known i<> "in- concbologuta that 



inson'a rugosut \~ tin: old shell of Say's Anodoniu tintluliitii, which wai de> 

 9cribecl from a young specimen, and has priority to (he 



