' The American Voles of the Genus Evotomys. loo 



General characters. — Size considerably less than caJiforuicus ; dorsal area 

 indistinct; tail long and slender ; concolor ears nearly naked, not large, 

 hut coiispicuons ahove the short smnmer far ; tail and feet scantily haired 

 in sinunier specimens ; lateral glands cunspicuous in 2 out of o adults from 

 Aberdeen. 



Color. — August specimens from Aberdeen : dorsal area ill defined, some- 

 times indistinct, varying from dull bnrnt umber to dark chestnut, dark- 

 ened by numerous black-tipjied hairs; sides dusky gray with a huffy 

 suffusion ; an oval patch of darker sooty gray covering side glands in the 

 typie and two other specimens ; tail almost concolor, blackish ; feet dusky 

 or blackish ; belly salmon-buff, the dusky under fur showing through ; 

 nose blackish. 



Cranial characters. — Skull thin and light, without prominent angles and 

 processes, relatively narrow and slender, with gently arching zygomata; 

 anterior part of palate from molars to incisors well arched ; audital buUre 

 much inflated, crowding close together over basioccipital ; pterygoids flat, 

 thin, and much perforated at base ; palatines with a rounded or notched 

 posterior i^rojection ; molars normal ; anterior surface of upper incisors 

 orange, in strong contrast to the pale yellowish of those of E. saturalas. 



^feasHrement!^. — Type, measured in the flesh by T. S. Palmer, (^ ad.: 

 total length, 145; tail vertebrje, 45 ; hind foot, 18. Average of 3 ad nlfs 

 from type locality : 146 ; 47 ; 18.3. Skull of type : basal length, 22 ; nasals, 

 7; zygomatic breadth, 12.5 ; mastoid breadth, 11 ; alveolar length of molar 

 series, 4.7. 



Remarks. — This species is peculiar to the low, moist coast and sound 

 region — the ' Webfoot country' — where its dark color blends with the 

 shadows of dense vegetation. In general the color is nearly as dark as 

 that of E. callfornicus, but the rich brown on the back, the concolor, 

 dusky tail, and dusky feet are the characters most sharply distinguishing 

 it from neighboring species. There is a possibility of intergradution with 

 E. valljontlcus on the south, as well as with E. sataraius of the mountains 

 fartlier east. Specimens from Port Moody, B. C, while agreeing closely 

 with the type in all external charactei's, show a slight departure in cranial 

 characters in the more angular skull, paler incisors, and smaller audital 

 bulhe. A half-grown specimen from the head of Cascade Eiver is slightly 

 lighter and brighter colored than specimens of the same age from the type 

 locality. 



Evotomys pygmicus Rhoads, from the mouth of the Nisqually River, 

 Washington, is based on small size, and was described as the smallest 

 species of the genus, measuring 120; 34 ; 16. In a series of 9 specimens 

 from Tenino (16 miles SW. of the mouth of Nisqualla River), adult speci- 

 mens, measured in the flesh by C. P. Streator, range from 136 ; 40 ; 18 to 

 155; 49; 18. Two not fully adult specimens from Steilacoom (8 miles 

 NE. of the mouth of Nisqually River) measure 125; 36; 16.5 and 128; 

 39; 17. In brief, specimens from Tenino and Steilacoom localities close 

 by and on both sides of the type locality of ' pygiinms' agree within the 

 limits of individual and slight seasonal variation in size, color, and cranial 

 characters with specimens from Aberdeen, the type locality of £■. occiden- 



