1911] Taylor: Mammals of the 1909 Nevada Expedition. 261 



of the soil in which they were found would indicate that they 

 were made by fisheri. 



All the adults showed unmistakable signs that mating had 

 taken place some time before. A male juvenal of the year was 

 caught July 5. A female secured July 2-4 (no. 7853) contained 

 six embryos. 



The gopher of the flat, TJiomomys nevadensis, was observed 

 for the most part in loose soil ; but equal numbers of workings 

 of the mountain species were recorded in very hard dry soil and 

 soft damp earth. The hardness of the soil seemed not to have 

 so nnich influence on the distribution of this gopher as some 

 other factor, probably the location of food plants. No workings 

 of fisheri more than twenty-five yards from water were seen. 

 Nevadensis seems to be confined even more closely to moist earth, 

 and consequently its distribution is more immediately dependent 

 on the location of streams. 



The only clue obtained to the exact food of fisheri was the 

 fact that the cheek-pouch of one of the specimens captured con- 

 tained the head of some composite flower and a small green stem. 



One example may be cited as showing how these little gophers 

 progress underground. Five mounds were noted arranged in a 

 slightly curved line, about three feet apart, and all about the 

 same size, namely, eight inches to a foot in diameter. The mound 

 at one end was quite new, that at the opposite end being the 

 oldest. A juvenal gopher was caught in the part of the burrow 

 leading to the freshest mound. The animal had moved under- 

 ground in a given direction, coming to the surface and throwing 

 out earth at definite intervals. 



In many instances it is difficult to locate open burrows in 

 the workings, as this gopher packs the exits very solidly full of 

 earth. Evidences of the former presence of gophers were ob- 

 served on several high meadows, where tubes of mud, built 

 through the snow when it lay heavy on the ground in winter 

 and left behind when it melted, were not infrequently seen. 

 Their activity does not appear to be inhibited wholly by cold 

 weather. For some reason, possibly disease or increase of 

 enemies, the species seems to be much less abundant at present 

 than it was a few vears ago. Among enemies whose increase 



