OF THE UPPER MISSOURI. 147 
taken alive, but all efforts to domesticate it were fruitless. It died after three days’ con- 
finement. Range: Missouri to Minnesota and Nebraska. 
THOMOMYS RUFESCENS, Maxim. 
Fort Union GopHer. Baird, General Report on Mammals, 1857, p. 397. 
This Gopher seems to take the place of the Geomys bursarius, from Fort Pierre to the 
mountains, but is similar in its habits. ‘Two specimens were taken at Fort Union, and 
one at Fort Randall. 
JAcuLUS Hupsonivs. 
_Jumpina Mouse. Baird, General Report on Mammals, 1857, p. 480. 
Only two specimens of this species were taken during the exploration, and they were 
collected near Fort Union. Range: Nova Scotia to Southern Pennsylvania, and west to 
the Pacific Ocean. 
PEROGNATHUS FLAVUS, Baird. 
Baird, General Report on Mammals, 1857, p. 428. 
Collected on the Loup fork, during the summer of 1857. Range: Upper Missouri, 
along eastern slopes of Rocky mountains to Sonora and Chihuahua, and along the Rio 
Grande to Matamoras. 
Dreopomys Orpir, Woodh. 
Kanearoo Rar. Baird, General Report on Mammals, 1857, p. 410. 
A single specimen of the above species was taken on the Niobrara river. Range: Platte 
river, along the eastern slope of the Rocky mountains, into Durango and Coahuila, Mexico. 
Mts muscuuvs, Linn. p. 443. 
Already quite abundant and troublesome at all the Fur Trading Posts on the Missouri. 
Mus ratius, or Common Rat, has also been introduced. 
HESPEROMYS SONORIENSIS, Leconte. 
Baird, General Report on Mammals, 1857, p. 474. 
Very abundant near Fort Union and along the Yellowstone Twenty-five specimens 
were collected. Range: Upper Missouri and Rocky mountains to El Paso and Sonora. 
HESPEROMYS LEUCOGASTER. 
Missourr Mouse. Baird, General Report on Mammals, 1857, p. 480. 
Very rare; but two specimens secured; one near Bijoux hills, the other on Vermilion 
prairie, and are the only specimens in the Musuem of the Smithsonian Institution. Very 
little is known of its habits, and it has been observed only on the Upper Missouri. 
