THE MAMMALS 



Moles. Scapanus latimanus (Bachman)^ 



Field characters. — Total length 6 to 6% inches (150-170 mm.), tail about IVz 

 inches (38 mm.); body short and cylindrical; snout long and pointed (fig. 4); forefeet 

 with greatly expanded and flattened palms and long heavy 

 claws (fig. 5a) ; tail scantily and coarsely haired; no eyes 

 or ears visible. Pelage short, soft, plush-like in texture; 

 coloration uniform, dark brown, gray, or blackish (accord- 

 ing to subspecies), appearing silvery when smoothed down. 

 Habits: Strictly subterranean; live in tunnels formed by 

 the animals themselves in the ground. Workings: Low 

 raised ridges (containing runways) along the surface of 

 ground; also, less commonly, mounds of earth mth irregu- 

 lar surface, erupted from underground tunnels, and with 

 no indication left of any opening to burrow (fig. 22). 



Occurrence. — Present in small to moderate numbers 

 locally across the Yosemite region; noted from Snelling 

 eastward to Mono Mills and up to an altitude of 9500 feet 

 (in Lyell Caiion) ; especially common in meadows of Yo- 

 semite Valley.i Individuals live and work independently. 



Fig. 4. Snout of Yo- 

 semite mole, from below, 

 showing elongate tip be- 

 yond mouth, short front 

 (incisor) teeth, and heavy 

 covering of hairs on sides 

 of face. Twice natural size. 



The mole and the pocket gopher, and the re- 

 spective workings of the two, are often confused 

 in the popular mind. The two animals, and their workings, however, are 

 entirely distinct in practically all respects save that both inhabit the 

 ground. In most places in California, and this includes the Yosemite 

 region, moles are much less common than gophers. This fact probably 

 accounts for some of the misunderstanding which has arisen. By careful 

 searching we found some evidence of moles at almost every locality which 

 we visited in the section (below the 9500 foot contour) from the San 

 Joaquin Valley eastward across the mountains to Mono Lake. On the floor 



1 Three slightly differing subspecies of moles occur in the Yosemite section. These, 

 with their principal external characters, and ranges, are as follows : 



Yosemite Mole, Scapanus latimanus sericatus Jackson, distinguished by relatively 

 large size and blackish coloration, is found in the Transition and Canadian zones, spar- 

 ingly in the Hudsonian, from 3 miles east of Coulterville eastward to Tuolumne Meadows. 

 It is abundant in Yosemite Valley. 



San Joaquin Mole, Scapanus latimanus campi Grinncll and Storer, a smaller, paler 

 and more brownish colored form, occurs in the Lower Sonoran Zone, at Snelling. 



Mono Mole, Scapamis latimanus monoensis Grinnell, a still smaller and grayish-toned 

 subspecies, was found near Williams Butte; its workings were noted at Mono Mills. 



The workings of these three races are alike in all respects, save for differences con- 

 ditioned by the various sorts of ground in which they occur. Thus the forage runways 

 of monoensis in the dry sandy soil of the Mono Lake region are more likely to be caved 

 in than are those of sericatus on the damp forest floor in the mountains. 



[43] 



