1897.] NATURAL SCIENCES OF PHILADELPHIA. 317 



of sooty on tail, feet and head, and in the whiteness of the hair of 

 nnderparts. The skin specimen, on the other hand, is between rus- 

 set and wood-brown above, the underside being washed with dirty 

 cream-buff and light Isabella color. The latter specimen has the 

 appearance of being once immersed in alcohol. The great length of 

 the hind foot (42 mm., when dry) and the general lightness of 

 underpartsare the only reliable characters in these specimens which 

 go to justify the specific separation of sabrinus and alpinus, and 

 their distinction from fuliginosus. 



In the third volume of their Quadrupeds of North America, 

 Audubon and Bachman undertook to redefine the alpinus of Rich- 

 ardson and appropriate the name to themselves. 8 They describe 

 and figure it from a specimen which we may infer from their ac- 

 count was taken by Townsend when crossing the Rocky Mountains 

 in southeastern Idaho. 7 Professor Baird, in commenting on this 

 specimen, remarks 8 : " There is a Flying Squirrel in the museum of 

 the Philadelphia Academy of Natural Sciences labelled ' Pteromys 

 alpinus, Columbia River, Dr. Townsend,' but I am unable to say 

 whether it is really the type of Bachman's description or not. The 

 locality is probably the Rocky Mountains, as described by Bach- 

 man, nearly all of Townsend's specimens having been labelled 

 Columbia River, whether collected there or on the overland march 

 from St. Louis." With this specimen in hand I find it difficult to 

 regard it as the type of Audubon and Bachman's description and 

 plate of alpinus. In both color and measurements it differs con- 

 siderably from their diagnosis. 



The second western Flying Squirrel to receive a new specific 

 name was the " Pteromys oregouensis " of Bachman described in 1839 

 in the Journal of the Academy of Natural Sciences of Philadelphia 

 from a specimen taken by J. K. Townsend in the " pine woods of 

 the Columbia River near the sea." This type specimen yet exists 

 in good condition in the collection of the Academy of Natural 

 Sciences of Philadelphia. It remains as originally mounted in the 

 flight position, with membranes widely extended, the limbs at right 

 angles to the body and the skull within the skin, apparently un- 

 broken. Though somewhat faded by exposure to the light it closely 



6 Quad. N. Amer., 1854, pp, 206-208. 



7 They made the mistake of thinking (1. c, p. 207) that Townsend crossed 

 the mountains by the same route as Drummond, and that the specimens of 

 each were topotypes ! 



s Mam. N. Amer., 1858, p. 2S9. 



