DONATIONS. 199 



Lea, I. Description of Six New Species of Fresh-water and Land 

 Shells of Texas and Tamanlipas, from the Collection of the 

 Smithsonian Institution. 1857. 



. Description of the byssus of the genus Vnio. 1857. 



Description of twenty - five new species of exotic 



Uniones. 1856. 



. Descriptions of eight new species of Naiades from 



various parts of the United States. 1857. 



Descriptions of eleven new species of exotic Uniones 



from Georgia. 1857. 



Descriptions of fifteen new species of exotic Melaniana. 



1857. 



. Descriptions of four new species of Exotic Uniones. 1857. 



Descriptions of six new species of Uniones from Alabama. 



1857. 



. Descriptions of thirteen new species of Exotic Periosto- 



mata. 1857. 



. Descriptions of thirteen new species of Uniones from 



Georgia. 1857. 



. Descriptions of three new species of Naiades. 1857. 



. Descriptions of twelve new species of Uniones from 



North Carolina. 1857. 



On the New Red Sandstone Formation of Pennsylvania. 



1856. 



. Remarks on Triquetra contorta. 1857. 



. Remarks on the visual organs of the Naiades. 1857. 



Leidy, J. A memoir on the extinct Sloth-tribe of North America. 

 1847. 



Description of Remains of Fishes from the Carboniferous 



Limestone of Illinois and Missouri. 1857. 



Descriptions of some Remains of extinct Mammalia. 



1856. 



. Descriptions of some Remains of Fishes from the Car- 

 boniferous and Devonian Formations of the United States. 1 856. 



. * Notice of Remains of the Walrus discovered on the 



Coast of the United States. 1857. 



Observations on the extinct Peccary of North America. 



1857. 



