34 



MAMMALOGY. 



The Beaver does not appear to have come under the notice of either 

 of the naturalists of the Expedition, neither in Oregon nor California, 

 but we find recorded in the journal of Dr. Pickering, memoranda of 

 information derived from residents in those countries, which are of 

 interest. At Fort Okanagan, he mentions: 



" It is said here, that the Beaver was formerly of common occur- 

 rence in all the streams, and that the Indians trapped it to some 

 extent. The fact that it is now almost extinct is attributed to the 

 introduction of traps of better construction, and to the unremitted 

 destruction of this animal for the sake of its skin. It is said to be yet 

 occasionally seen." 



In California, he states : 



"I am informed by Dr. Marsh that the Tide districts abound in 

 Beavers, and that from the peculiar character of those localities it is 

 very difficult to take them in traps. It is said, too, that this animal 

 is found on the Sacramento River, but no sign of it was seen by our 

 jjarty, so far as our boat voyage extended." 



2. Genus FIBER, Cuvler, Reg. An. I, p. 192 (1817). 



1. Fiber zibethicus {Linn.). The Muskrat. The Musquash. 



Castor zibethicus, LiNN. Syst. Nat. I, p. 79 (1766). 



Aud. and Bach. Quad, of N. A. Plate XIII, Oct ed. I, Plate XIII. 



This animal is mentioned by the naturalists of the Expedition as 

 having been observed in Oregon, and the same has been done by 

 other travellers. We are not aware, however, that any specimens 

 from Western North America have ever reached the collections in the 

 Atlantic States, or that any comparison with the common species of 

 the Eastern United States has ever been made, which, from Mr. Peale's 

 statement below given, relating to the size of western specimens, we 

 regard as quite important for the more exact determination of the 

 species. 



This species, if indeed it is identical with the well-known Fiber 

 zibethicus of the Eastern States, appears to inhabit the entire coast of 

 Oregon and Russian America, and is given by Pallas, in Zoographia 

 Rosso-Asiatica (I, p. 144), as an inhabitant also of Siberia. 



