88 VERTEBRATES I MAMMALS. 



The Rocky Mountain Flying Squirrel, P. alpinus, 

 Rich., has the lateral membrane with the border 

 straight, and the tail longer than the body exclusive 

 of the head. 



The Columbia River Flying Squirrel, P. oregonensis, 

 Bach., is seven inches long to the tail, which is over six 

 inches, the color yellowish brown above, and dull white 

 beneath. 



The Taguan, P. fetaurista y Linn., of the Indian Archi- 

 pelago, is nearly as large as a cat, the male a lively mar- 

 roon above and red beneath ; the female brown above. 



It must not be inferred from the name of the Flying 

 Squirrels that they perform anything like true flight. On 

 reaching a point on one tree from which they would move 

 to another, they make a leap, at the same time stretch- 

 ing their fore legs forward and their hind legs backward 

 and outward, thus expanding the lateral fur membrane, 

 above described, and so glide to the point aimed at. 

 This point is rarely more than one third of the height 

 of the one from which the squirrel starts. Having gained 

 one point in this manner, they quickly ascend the tree to 

 a suitable height, and then spring forward again. And 

 in this way they can make their way through the forest 

 quite rapidly. 



The Common Flying Squirrel is a very gentle species, 

 and is very easily tamed. It is very quiet during the 

 daytime, but very lively and playful at night. 



The Genus Tamias Striped Squirrels is charac- 

 terized by ample cheek pouches, tail shorter than the 

 body and not bushy, three to five dark dorsal stripes, 

 and four permanent upper molars. This genus comprises 

 only a few species, two of which are found in Europe and 

 Asia, and the remaining four or five in North America. 



The Chipping, Striped, or Ground Squirrel, or Chip- 



