1936] 



MAMMALS OF OREGON 



355 



east side of the Cascades, but generally they belong to the humid 

 coastal slope or " web-foot " country, in mainly Transition Zone. 

 They are generally found in swampy places, marshes, meadows, or 

 sometimes under logs in the dry woods. 



General habits. These tiny moles are apparently shrewlike in 

 habits, living partly underground in their own little tunnels but 

 also pushing about under the leaves and grass on the surface of the 

 ground, or through the soft mold of old decaying logs. Occasionally 

 they are caught in mousetraps set in runways of meadow mice and 

 other ground-living rodents and shrews, indicating a life lived partly 

 on the surface of the ground. Their small eyes are probably of some 

 service in their quest for insect food, and the long flexible nose is 

 well fitted for detecting 

 food under cover of the 

 soft earth where they 

 hunt. 



Food habits. The na- 

 ture of their food can be 

 guessed from the highly 

 specialized insectivore 

 teeth and from the finely 

 masticated remains of 

 worms and various insects 

 found in the stomachs of 

 those collected for speci- 

 mens. 



At Crater Lake, Preble 

 caught one in a mousetrap 

 baited withf resh meat and 



set in a hollowed-out place under an old log. At Fort 

 he caught four in a patch of willows and alders on the bank 

 River by baiting his traps with bacon. They were evidently 

 from their burrows by the odor of the bait. 



Economic status. Like the shrews these little moles are entirely 

 harmless, and may even be highly beneficial from their help in control- 

 ling the abundance of ground and underground insects and other 

 small life. 



Family SORICIDAE: Shrews 



SOREX PALUSTRIS NAVIGATOR (BAIBD) 

 ROCKY MOUNTAIN WATER SHREW 



Neosorex navigator Baird, Mamm. North Amer., p. 11, 1857. 



Type. Collected at Yakima River, Cascade Mountains, Wash., by J. G. 

 Cooper, August 31, 1853. 



General characters. Size large, tail about as long as head and body; feet 

 large; sides of feet and toes heavily fringed with silvery bristles for swimming; 

 nose long and pointed; eyes minute; ears short and wide and almost con- 

 cealed in fur; body covered with dense, soft, velvety fur; feet and tail thinly 

 haired. Color : Above blackish or plumbeous, finely flecked with hoary ; below 

 light gray or whitish over plumbeous underfur; feet plumbeous gray with 

 silvery margins ; tail blackish above, whitish below. 



Measurements. Adult male from Mount Rainier : Total length, 152 mm ; tail, 

 78.; foot, 19. Weight of 12 males 8.3 to 15 g (Grinnell, Dixon, and Linsdale, 

 1930, p. 452). 



FIGURE 83. Range of Gibbs's mole, Neurotrichus 

 ffibbsii gibbsii, in Oregon. 



Klamath 

 of Wood 

 attracted 



