322 PROCEEDINGS OF THE ACADEMY OF [1897. 



outer surfaces of ears drab-gray ; sides of head smoke-gray. A nar- 

 now circle of blackish slate surrounds the eyes; whiskers black. 



Cranial characters. — Presumably as in dlpinus. Compared with 

 sabrinus from Maine the skull is much larger, more elongate and 

 depressed. The greatest width of parietals is less than their great- 

 est (lateral) length, whereas in sabrinus these proportions are re- 

 versed. In adult fuliginosus the widths of frontal constriction be- 

 fore and behind the postorbital processes are about equal ; in sabrinus 

 the posterior width greatly exceeds the anterior interorbital con- 

 striction. Owing to the interorbital depression of frontals and their 

 postorbital inflation, together with the pug-nosed shape of the nasals 

 in sabrinus, the lateral facial profile of that species is decidedly 

 dished. In fuliginosus the facial profile is straight, or in some cases 

 slightly convex. The incisors in sabrimis are deep chrome, in fuli- 

 ginosus and its western allies they are orange-rnfous. 



Dimensions (of type taken in flesh). — Total length 317 millime- 

 ters ; tail vertebra? 153 ; hind foot 40 ; ear, from crown (relaxed) 

 18 ; length of carpal fascia 25. Average of 3 adults from type 

 locality (in above order) : 310 ; 146 ; 41.5 ; 17 ; 26. Skull of type: 

 occipito-nasal length 40 ; greatest breadth 23.8 ; length of nasals 

 13 ; frontal constriction behind postorbital processes 9 ; interorbital 

 constriction 8.2 ; greatest length of mandible 23.2. Average of 3 

 adults from type locality (in above order) : 41 ; 24 ; 12.8 ; 8.5 ; 8 ; 

 24.2. 



General remarks. — Subspecies fuliginosus, from its close resem- 

 blance to all the characters justly assigned to alpinus by Richardson 

 and Bachman, is nothing more than a dark race of the Rocky 

 Mountain animal and equal to if not exceeding it in size. The 

 Stuart Lake specimen, already referred to under alpinus, closely re- 

 sembles fuliginosus, differing only in slightly smaller size, browner 

 back and blacker face in the direction of oregonensis, confirming the 

 supposition of a complete intergradation between the two at inter- 

 mediate elevations. From what we know of the fauna and flora of 

 the Selkirk Range, it is probable that the Flying Squirrel of those 

 mountains is nearer fuliginosus than alpinus. The form living in 

 the lowlands of the upper Great Basin, the existence of which near 

 Vernon, B. C, I once had great reason to remember, but which an 

 unfortunate encounter with hornets prevented me from obtaining, 

 would be of great interest. It is, so far as I can remember from a 

 hasty but vivid view in life, a distinctly smaller, lighter colored 

 animal than fuliginosus. 



