OP 00NCHOLOQY. 10? 



DESCRIPTION OP A NEW SPECIES OF UNIO. 



BY T. A. CONEAD. 



Unio depygis, Conrad. — PI. 10, fig. 1. 



Description. — Short, suboval, subcompressed, beaks situated 

 behind the middle ; disks slightly tumid medially ; posterior 

 side flattened or slightly contracted ; opposite ventral margin 

 truncated ; anterior ventral and anterior margins regularly 

 rounded ; posterior margin truncated, direct ; beaks undulato- 

 plicate; epidermis olivaceous, indistinctly rayed posteriorly, 

 and clouded with dark green about the umbo; anterior car- 

 dinal tooth long and very oblique. 



Locality. — Harpeth Eiver, Tennessee. W. H. DeCamp, M. D. 



Cabinet of Dr. Wm. H. DeCamp, Grand Rapids, Mich. 



Observations. — More compressed than U. lens and less pon- 

 derous. It is also a larger species, and very peculiar in hav- 

 ing so short a posterior side and no obliquity of outline. 



