tfi OBSERVATIONS ON NAIADES, 



their being embodied in one paper with those which I was about to 

 publish. This species somewhat resembles U. triangularis of Barnes. 

 It differs from it in being less ventricose, more ponderous, possessing 

 thicker teeth and in the rays which are interrupted indistinct lines. 



Unio Pustulosus. Plate VII. fig. 7. 



Testa modice productd, aquilaterali, inflata, dimidio postico tuber culata ; valvti- 

 lis crassis; natibus prominentibus et ad apices granulatis; dentibus cardinalibus 

 subgrandibus ; lateralibus brevibus, crassis, rectisque; margaritd alba et ir'ides- 

 cente. 



Shell rather elongated, equilateral, inflated, tuberculated on posterior half; valves 

 thick; beaks elevated and granulated at tip; cardinal teeth rather large; lateral 

 teeth short, thick and straight ; nacre pearly white and iridescent. 



TT , C Ohio, T. G. Lea. 



l Alabama river, Judge Tait. 



My Cabinet. 

 Cabinet of Professor Vanuxem. 

 Cabinet of P. H. Nicklin. 

 Cabinet of H. C. Carey. 

 Cabinet of the Academy of Natural Sciences of Philadelphia. 

 Cabinet of Peale's Museum. 

 Unio verrucosus. Var. 6? Barnes. 

 Diam. 1-4, Length 2-2, Breadth 2-1 inches. 



Shell rather elongated, equilateral, inflated, irregularly tuberculated 

 on posterior half, but not on the first and second growths ; tubercles 

 generally large ; substance of the shell thick ; beaks elevated and 

 granulated at tip ; ligament short and thick ; epidermis bright brown ; 

 a single broad interrupted ray passes from the beak nearly to the cen- 

 tre of the disk ; cardinal tooth rather large and widely cleft in the 

 left valve — single and emerging from a pit in the right valve ; lateral 

 teeth short, thick and straight; anterior and posterior cicatrices both 

 distinct; dorsal cicatrices situated on the under part of the cardinal 



