360 



NORTH AMERICAN FAUNA 



[No. 55 



in the forests. Some are caught in traps baited with fresh meat, and 

 others in traps baited with rolled oats into which they may have 

 blundered in following runways of meadow mice. 



SOIIEX OBSCURUS OBSCURUS MERRIAM . 

 DUSKY SHREW 



Sorex obsourm Merriam, North Amer. Fauna No. 10, p. 72, 1895. 



Type Collected at Timber Creek, Lemhi Mountains, Lemhi County, Idaho 

 August 26, 1900, by Vernon Bailey and B. H. Dutcher. 



General characters. Size small, tail less than length of head and body; 

 nose long and pointed ; eyes minute, ears mainly hidden in the fur ; feet slender 

 and not noticeably fringed ; fur over body in summer short and rather harsh, 

 in. winter long and lax ; feet and tail thinly haired. Color : In summer pelage 

 dull tobacco brown over upper parts, lower parts buffy gray ; in winter darker 

 above and more silvery below. 



Measurements. Average typical specimen: Total length, 110 mm; tail, 47; 

 foot, 13. Type : 111 ; 46 ; 13. 



Distribution and habitat. From a wide range extending from 

 central Alaska through the Kocky Mountains to central New Mexico 

 this little brown shrew comes into the Blue Mountains of north- 

 eastern Oregon, where 

 specimens have been taken 

 at WallowaLake,Wallowa 

 Mountains, and Anthony 

 (fig. 87). Generally a 

 Canadian Zone species, it 

 sometimes comes down 

 along cold mountain 

 streams to lower levels. 



General habits. These 

 little brown, long-nosed, 

 soft-furred animals are 

 generally common in wet, 

 grassy places along 

 streams or under the cover 

 of logs, rocks, bushes, and 

 leaves in the dry forest of 

 the mountains. They keep 

 well under cover and are rarely seen, but occasionally one crosses a 

 trail or some open spot and gives the observer a glimpse of its tiny 

 form or pokes its long flexible snout out of a burrow and waves it 

 rapidly about in an inquiring way as if depending more on scent 

 and feeling than on eyesight. In the mellow woods earth around 

 and under old logs their tiny burrows often honeycomb the ground, 

 or a network of tiny runways may be found between the soft cover 

 of fallen grass and leaves and the surface of the ground. Most of 

 these seem to be mere plowings for food and not regularly used as 

 are the runways of rodents, but the shrews are great wanderers and 

 are frequently caught in traps set across the runways of meadow 

 mice, or in small burrows of other rodents. In winter their lines 

 of tiny tracks are often seen over the soft snow, usually ending in 

 little burrows where they readily return to the surface of the ground. 



FIGURE 87. Range of four shrews in Oregon : 1, So- 

 rest; oltscurus obscurus ; 2, S. o. Ixiirdi; 3, S. o. 

 permiliensis ; 4, S. o. setosus. Type localities cir- 

 cled. 



