126 ZOOLOGY. 



yellow. Males: Penis osseous, obscurely bifurcated, knobbed; testes concealed; no external 

 scrotum. 



They prefer to make their burrows in the rich ground near springs, perhaps partly influenced 

 in choice of this selection by proximity to certain kinds of food. Before blankets and civilized 

 clothing had become extensively used by the Indians of the northwest, many were in the habit 

 of making robes and garments of the skins of these animals, by stitching them together. 



Habitat. — Washington Territorj^ from the eastern bases of the Cascade mountains west to 

 the ocean. ? Northern Oregon. 



Three specimens sent by me to Washington are now in the Smithsonian collection. Several 

 others, which I had preserved in alcohol for dissection, &c., were subsequently lost on their 

 passage to the above named city. — S. 



Note. — Mr. Gibbs writes: "I find the Lewis and Clark's name of Sewellel for A. Icpovma is 

 an error. The Chinook name for the animal itself is o-givool-lal. She-iual-lal {Scwclkl, corrupt) 

 is their name for the robe made of its skins." 



CASTOR CANADENSIS, Kuhl. 

 Beaver 



Baird. Gen. Rep., Mammals. 1857, 355. 



The beaver and the land otter, particularly the former, have multiplied rapidly since the 

 fur trade has become of such little value. I am told that they are now in greater numbers than 

 they have been at any time since the first flush of the trade. The natives no longer seek them, 

 as they get clothing from the whites, and also because the skins bring such small returns, a 

 dollar being the present price of a large beaver skin in the stores. The Hudson Bay Company 

 give much less for them in trade. — G. 



I sent several hunters' skins of the beaver, which I had obtained in Washington Territory, 

 to the Smithsonian museum. Beavers are very common on the small streams in the Cascade 

 mountains, and, as Mr. Gibbs says, are apparently increasing. I saw a "beaver dam" at the 

 outlet of a small pond near Cedar river, W. T., which in all essential particulars resembled 

 those I saw of the same animal in the Rocky mountains. — S. 



THOMOMYS DOUGLASII, Giebel. 



Colombia Gopher ; Poached Rat. 



[For extended synonymy and Sp. Ch., see chap. 2, p. 100,] 



The pouched rat is very abundant on the Nisqually plains. It is very destructive to potatoes, 

 while in the ground, carrying ofi" large quantities of the smaller ones and cutting the vines. — G. 



The natives at Fort Steilacoom (Nisquallj-s) call the gopher mes-Jca-dah, or the thief. These 

 animals are very abundant on the gravelly prairies near Nisqually. They prefer the richer 

 and less gravelly portions in the hollows and swales, as well as spots along the edges of the 

 prairie brooks where the soil is good. In fact, the settlers look upon the presence of their 

 peculiar mounds or hillocks as a sure indication of rich soil. These mounds are about three 

 inches in height at their summits, and from nine to fifteen inches in diameter — rarely, 

 however, exceeded ten or twelve. Although, on account of their tendency to "cave in," 

 they are somewhat dangerous for horses to travel over, they, nevertheless, are not near so 

 dangerous as similar heaps thrown up by the gophers of Minnesota, which will rarely stand the 

 pressure of a horse's foot, as they are larger, and their cavities greater than those of the 

 present species. In Minnesota these "gopher hills" are extremely common on the buffalo 



