SECTION B.] NORTH AMERICAN CONCHOLOGT, 



55T 



[Proceedings Academy of Natural Sc] 



May, 1858. 

 Page. 



118 Lea. — Description of four new Fresh Water Mollusca from the 

 Isthmus of Darien and Honduras : hy Isaac Lea. 



118 Unio Cald-wellii Lea. 



118 Goascoranensis Lea. 



118 Anodonta luteola Lea, 



118 Melania planensis Lea. 



May, 1859. 



151 Liea.> — Descriptions of twenty-one new 

 by Isaac Lea. 



151 Unio Sikkimensis Lea. 



151 diminutis Lea. 



152 plicatulus Lea. 



152 navigioliformis Lea. 



152 fluctiger Lea. 



152 mutabilis Lea. 



152 Th-waitsii Lea. 



152 melleus Lea. 



152 Dysoni Lea. 



152 Demararaensis Lea. 



152 Mauritianus Lea. 



153 vittatus Lea. 



153 Shanghaiensis Lea. 



153 Layardii Lea. 



153 Japanensis Zea. 



153 Sumatrensis Lea. 



153 Rowellii L.ea. 



153 "Wilsoni Lea. 



154 Anodonta Dahomeyensis Lea. 

 154 Senegalensis Leu. 



Isthmus of Darien. 

 Eiv. Goascoran, Honduras. 

 Isthmus of Darien. 

 Plan, &c., Honduras. 



species of Exotic Unionidse : 



Sikkim, India. 

 East Africa. 

 Borneo. 



Australia, &c. 

 Ceylon. 



Honduras. 



Demarara. 



Mauritius. 



Australia. 



Shanghai. 



Ceylon. 



Japan. 



Sumatra. 



Chagres riv., N. Granada. 



Isaac's Plain, N. S. W. 



Dahomey. 



Senegal. 



July, 18.i9. 

 187 L.ea. — Descriptions of four new species of Exotic Unionidse : by 

 Isaac Lea. 



187 Unio bulloides Lea. 



187 Monochondylaea planulata Lea. 



187 rhomboidea Lea. 



187 Unio rudu8 Lea, 



R. de la Plata. 



Java. 



Euphrates, near Bagdad. 



R. de la Plata, 



Oct. isr,9. 



281 L,ea. — Description of a new species of Unio from the Isthmus of 

 Darien : by Isaac Lea. 



281 Unio Averyi Lea, 



Isthmus of Darien. 



