ZOOLOGY. 381 



Family ARCADE, 

 ARCA GRANDIS. 



drcagrandis Bnon. & SOWERBY; REEVE, C. I., pi. , f. 4. CARPENTER, Report, p. 310. 

 Hab. San Diego; Mr. Cassidy. 



A fine specimen of this remarkable Area, preserved entire in alcohol, was sent to the Smith 

 sonian Institution from San Diego by Mr. Cassidy, being the first instance in which it has 

 occurred beyond the limits of the Panama province. 



Family UNIONIDJ1, 

 MARGARITANA MARGARITIFERA. 



Margaritana margaritifera, LEA, in Philos. Trans. 

 J\Iya margaritiftra, LINN. 

 MargaritanafluviatHis, SCHUMACHER. 



Masmodonta falcata, GOIJLD, in Proc. Bost. Soc. N H. HI, p. 294. IDEM, U. S. Exploring Ex. Mollus. & Sh. 

 pp. 433, 434 CARP. Report, p. 309. 



Hab. Chehalis and other rivers of Washington Territory; Dr. Cooper. Shasta river, Oregon; Dr. Trask. 



After a careful comparison of specimens from the above localities with others from the 

 Atlantic States, as well as from Newfoundland and Europe, we are brought to the same 

 conclusion as Mr. Lea, namely, that the northwestern shell is at most a slight variety of the 

 the well-known M. margaritifera of Linnaeus. 



This is the most abundant of the fresh water bivalves, and the only one I have been able 

 to find in the Chehalis, the streams emptying into Puget Sound, and most branches of the 

 Columbia. No species is found in the streams running into Shoalwater bay. The Indians east 

 of the Cascade mountains eat these, food of any kind being acceptable to most of them.&quot; C. 



ANODONTA ANGULATA. 



.I n mlnn t u angulata, LEA, in Philos. Trans. 



Jlnodontafccminalis, GOULD, U. S. Expl. Exped. Moll, and Shells, 436. CARP. Rep. p. 309. 

 Hab. Yakima river, Washington Territory; Dr. Cooper. Walla-Walla river, Oregon, Dr. Pickering. 



Several perfect specimens of various ages were brought by Dr. Cooper from the above 

 locality, where it appears to be plentiful. 



ANODONTA OREGONENSIS. 



rfnodonla oregonensis, LEA, Philos. Trans.; pi. xxi, f. 67. CARPENTER, Rep. p. 309. 

 Hab. Rivers of Washington Territory; Dr. Cooper. 



ANODONTA WAHLAMATENSIS. 



Jlnodonln wahlamatcnsis, LEA, in Philos. Trans.; pi. xxi, f. 64. CARPENTER, Rep. p. 309. 

 Hab. Lagoons, Sacrament; Dr. Trask. Wahlamet river; Nuttall. 



The Californian specimens sent by Dr. Trask are larger and finer than those from the more 

 northern habitats. 



