78 ^filler — Synopsis of the Voles of the Genus Phenacomys. 



one huiulred well-prepared skins available for examination.* 

 This material shows that, of the nine described forms, the fol- 

 lowing six are valid : 



Name. Ti/jh' loculily. 



P. intermedins Merriani KtiuiloopK, Britisli Columbia. 



P. orophilus Merriam Salmon River Mountains, Idaho. 



P. pirhlei Merriam Longs Peak, Colorado. 



P. latiimiiiiix ^lerriam Fort Chimo, Ungava, Labrador. 



P. un<jai-(i INIerriam Fort Chimo, Ungava, Labrador. 



P. Inuijicaiidnx True Marshfleld, Coos County, Oregon. 



These fall naturally into three groups, each of which occupies 

 a different geographic region. The ungava group, containing 

 two well-marked yellow-faced species, ungava and Jatimanus, 

 ranges from Quebec and Labrador west at least as far as the 

 north shore of Lake Superior. The intermedrus group, with 

 three slightly differentiated uniformly grayish or ochraceous 

 species, tntcrmedius, orophilus, and jnrttlei, occupies the moun- 

 tains of British Columbia, Alberta, and the northwestern United 

 States. The third or longicaudns group is represented by one 

 species only, the very aberrant P. longicaudus of the humid coast 

 district of Oregon. 



The species of PJienacomys are voles of medium or small size. 

 With the exception of P. lon.gicaudus, which is remarkable for its 

 very long tail, there is nothing in the external appearance of any 

 to distinguish them from small si)ecies of Microtus. They gen- 

 erally inhabit dr^', grassy plains and mountain parks, but P. 

 longicaudus appears to be strictly arboreal. At present all the 

 species detinitely known are American. The determination of 

 the European fossil remains is open to question. f 



*The specimens examined in the present connection are distributed as 

 follows : U. S. National Museum, 04, including the types of P. longicaudus, 

 P. oropliilus, P. truei, and P. prehlei (all but two of these are in the Bio- 

 logical Survey collection) ; INIuseum of the Canadian Geological and Nat- 

 ural History Survey, 1 (type of P. intermediufi) ; Merriam collection, 3 

 (types of P. celutiis, P. ungava, and P. Iidiinaiiinf) ; Bangs collection, Ki 

 P. ungava from Hamilton Inlet, Labrador; IMiller collection, 7 P. lati- 

 initiius from the north shore of Lake Superior, and 4 P. urnphilns from 

 Mount Baker, British Columbia (topotypes of P. (iramoidis). 



tSee North American Fauna, No. 12, p. 40. 



