THE HARRIMAN ALASKA EXPEDITION 27 



Cranial characters.— '&V\x\\ similar to that of L. Icmmus but 

 slightly smaller; braincase smaller and less flattened; zygomata less 

 widely spreading; angle of mandible much less everted; upper in- 

 cisors heavier (broader). Compared with nigrlpes from the Pribilof 

 Islands the differences are more marked : skull decidedly smaller and 

 less massive ; nasals much shorter and smaller ; rostrum more slender ; 

 frontals not elevated into tubercles anteriorly; bull^ larger (more 

 broadly indated) ; angle of jaw much smaller and less everted. Molar 



series shorter. 



Measureme7its.—Tyy^^ specimen (measured from alcohol by C. H. 

 M.) : total length 115 ; tail vertebra; 15 ; hind foot 18. 



LEMMUS YUKONENSIS sp. nov. Yukon Lemming. 



Typeh-om Charlie Creek, Yukon River, Alaska. No. 98849 ? ad. 



U. S. National Museum, Biological Survey Collection. Aug. 9, 



1899. W. H. Osgood. Orig. no. 769. ^ 



Characters.— S\zc small, ears relatively large; general color dark 

 anteriorly, with bright fulvous or rufous rump and flanks; audital 



bullce immense. 



Co/or.— Head, shoulders, and anterior half of back grayish brown, 

 grizzled with black and yellowish fulvous, darkest on top of nose ; 

 rump and hinder part of back rich rusty fulvous or orange fulvous; 

 lower sides and belly golden fulvous ; deepest and brightest on flanks ; 

 sides of nose grayish or grayish brown ; a band of golden fulvous on 

 lower part of face from nose to below ear ; fore and hind feet dusky ; 

 tail bicolor, dusky above, buffy below. 



Cranial characters.— '^\^yx\\ very different from any species known 

 to me: braincase (seen from above) large, broad, ^nA produced pos- 

 teriorly to cover the enormously enlarged bulla;; frontal narrow inter- 

 orbitally, with a narrow median sulcus, but not ' pinched in' as in L, 

 alascensis; rostrum small; zygomata squarely set but not widely 

 spreading, the sides parallel; interparietal large, usually pentagonal; 

 incisive foramina rather short ; bullce remarkably large and strongly 



inflated. 



Measureme7tts.—{Yxom well made dry skin:) total length 130; 



tail vertebrae 17; hind foot 19.5. 



ERETHIZON EPIXANTHUS MYOPS subsp. nov. 

 Alaska Porcupine. 



Tvte from Portage Bay, Alaska Peninsula. No. 59140 9 old, U. S. 

 * National Museum. September 1893. Chas. 11. Townsend. 



