ZOOLOGY. 



123 



abundant, and animals apparently identical are quite common in the Blue mountains of Oregon. 

 No individuals of this species were observed by either Dr. Cooper or myself north of the 

 Columbia. They hibernate during winter, and are not seen until about the 1st of April, when 

 they make their appearance on fine days. At first they are apparently feeble and still very 

 sluggish in their movements, so that if they venture a short distance from the mouths of their 

 burrows they are readily killed with sticks or stones. Later in the season they are quite active, 

 and very rat-like in their movements and habits, which, however, are principally diurnal. In 

 summer they are quite fat, and are said to be very good eating when cooked. Their burrows 

 are entered by small round holes, which are but little larger around than the bodies of the full 

 grown animals. 



They do not burrow, like prairie dogs, in villages, at least they are not. markedly gregarious, 

 but seem to be governed in their choice of localities by the abundance of food. From their 

 marked preference for oak groves I should judge that acorns form a considerable part of their 

 sustenance. S. 



CYNOMYS LUDOVICIANUS, B a i r d . 



Prairie Dog. 



[See chap. 2, p. 29.] 



In 1849 the mountaineers told me that this animal is confined to the vicinity of the waters 

 which flow into the Missouri, and that upon crossing the water-shed and entering Oregon they 

 are replaced by a &quot;large squirrel,&quot; living in the rocks, which resembles the &quot;dog,&quot; but does 

 not &quot;bark.&quot; The Indians, they say, make robes of its skin. Probably this latter is the 

 Douglass spermophili which exists in great numbers on the Columbia, east of the Cascades. G-. 



In crossing the continent by land, in 1853, our party found &quot;prairie dogs&quot; in great numbers 

 all along its route through Nebraska, following the line of the Upper Missouri and its tribu 

 taries. They occurred in the Rocky mountains themselves, on the Dearborn river, and far up 

 the Blackfoot Pass, on the eastern slope of these mountains, to a point not far from the 

 &quot;divide.&quot; They may cross and extend a short distance in Washington Territory, but I think 

 that the western slope of the mountains is too heavily timbered for them. 



Townsend speaks of their being found in Oregon, but this active and really praiseworthy 

 naturalist allowed his specimens and notes to become so &quot;mixed up,&quot; that at last, finding so 

 many of his statements erroneous, naturalists sometimes doubt his testimony, unless further 

 backed up by that of others. I have inquired of many old settlers and others, reliable men, 

 none of whom corroborate Dr. Townsend s statement. In Nebraska their &quot;towns&quot; are situated, 

 in many instances, long distances from water, in places where it frequently does not rain for 

 six or eight months at a time, and where dew scarcely falls. It is for this reason supposed that 

 they burrow sufficiently deep to reach water. One kept alive by me rapidly became tame. 



Measurements of three specimens obtained on Milk river, Nebraska Territory. 



Eyes black. S. 



