1919] Dixon: Bushy-tailed Wood Bats of California 61 



The persistent musky odor which is characteristic of these rodents 

 is frequently the most reliable indication of their presence. Dissection, 

 by the author, of a particularly musky individual revealed well 

 developed anal or "musk" glands which were the obvious sources of 

 the musky odor. In this regard these wood rats are similar to the well 

 known muskrat. 



HOUSES 



House or nest building tendencies are not markedly developed 

 among the bushy-tailed wood rats of California. Wlien "houses" are 

 built they are usually so small that they could be placed entire within 

 a medium sized wash tub. At Jackson Lake, Siskiyou County, Kellogg 

 (MS) found one "placed under a big rock where the rats had carried 

 in a great quantity of sticks but had not built them into any sort of a 

 nest, the sticks being merely strewn over the flat space under the 

 rock. ' ' In the Panamint Mountains, Inyo County, a house composed 

 almost entirely of dead pinon twigs and bark, was found by the present 

 author about eight feet above the ground in a crevice between two 

 huge vertical slabs of granite which crowned the highest hill (7200 

 feet) in the vicinity. This house (see pi. 2, fig. 4) was sixteen inches 

 wide, almost as high, and extended back three or four feet into the 

 crevice. In this case the house was evidently used merely as a tempo- 

 rary refuge since it contained no inhabitants, although the new sticks 

 and freshly cut foliage showed that the house was of very recent 

 construction. 



The sticks used by the bushy-tailed wood rats in constructing such 

 houses are usually of small size, much less than one inch in diameter 

 and less than a foot in length. In the Mount Wliitney region, W. P. 

 Taylor (MS) states that there were many sticks in rock crannies which 

 appeared to have been brought in for nest building purposes, the 

 largest of which was about % inch in diameter and twelve inches long. 

 At an altitude of 9500 feet on Little Cottonwood Creek in the same 

 region, the same observer found "in one crevice a good number of 

 sticks and twigs, ranging from small size up to sticks a foot long and 

 an inch through. In the majority of places where wood rats have 

 been trapped no signs of nest building have been observable, but they 

 evidently, sometimes at least, make a pretense at nest building, ' ' 



