THE IIARRIMAN ALASKA EXPEDITION I7 



C/iaracfcrs. — Size large; tail rather sliort ; coloration strikingly 

 peculiar: bicolor in winter ; tricolor in .summer; the drab brown of 

 back restricted to a sharply dellned dorsal area in strong contrast to 

 paler color of sides, which in winter is silvery, in summer overlaid 

 with a brownish wash. The only related species having the same 

 pattern is the larger and very much darker S. richardsoni^ whose 

 sides are never silvery. 



Color. — SniiiDicr pclag-c (tricolor) : top of head and broad dorsal 

 area brown (usually drab brown) ; flanks and sides abruptly paler, 

 usually pale buffy brown; underparts soiled whitish; tail above 

 brown, becoming dusky all round at tip, below buffy. Winter pel- 

 age (bicolor): dorsal area drab brown, darkest posteriorly; flanks, 

 sides, and underparts silvery whitish in striking contrast. Owing to 

 the much greater length of fur in winter the animal appears larger. 



Cranial characters. — Skull and teeth (31I unicuspid larger than 

 4th) as is 6". ricJiardsoni.^ but slightly smaller ; constriction slightly 

 broader; large premolar and unicuspidate series smaller and shorter. 



jSIeasitrenieiits. — Type specimen : total length loS ; tail vertebra) 

 33; hind foot 13. Average of ten adults from type locality: total 

 length loS; tail vertebne 32 ; hind foot 13 (the same as the type). 



SOREX PERSONATUS ARCTICU.S subsp. nov. Arctic Shrew. 



Type from St. Michaels, Alaska. No. 99305 9 ad. U. S. Na- 

 tional Museum, Biological Survey Collection. Sept. 14, 1899. W. 

 H. Osgood. Orig. no. 910. 



^'wxvA-^x \.o persoiatushwi slightly larger ; tail larger; color much 

 paler, particularly on underparts, which in both summer and winter 

 pelages are conspicuously whiter. In summer pelage the upperparts 

 are pale drab brown, the underparts ashy whitish. In winter pelage 

 the fur is much longer and fuller; the upperparts dusky brownish 

 with a fine 'pepper and salt' appearance; the underparts (encroach- 

 ing on Hanks) silvery whitish with only the palest buffy suffusion, 

 and this sometimes absent. The skull is slightly longer than in 

 personatus ; the unicuspidate teeth decidedly larger. 



Contrasted with subspecies strcatori^ which it resembles in size, it 

 differs markedly in coloration, being very much paler both above and 

 below, and lacking entirely the brownish fulvous wash on the under- 

 parts. 



Measurements. — Type specimen: total length loS; tail vertebrae 

 39; hind foot 12. Average of teii adults from type locality : total 

 length 103; tail vcrtebric 37; hind foot 12. 



