THE GROUND SQUIRRELS OF CALIFORNIA. 657 



feet. The greatest depth reached beneath the surface of the ground was 

 45 inches. This was in rather dry pasture, and there was no sign of 

 a water-table ; the soil to this depth was only moderately damp. 



The notes of the Oregon Ground Squirrel are of two sorts. The 

 most impressive consists of a series of from 8 to 12 shrill, high-pitched 

 calls, uttered in rapid succession — seep, seep, seep, seep, seep, seep, seep, 

 seep, seep. The tendency is to weaken on the last few syllables, but 

 the same pitch is nearly or quite maintained throughout. This call 

 seems to be uttered only by adults, and seems to signify alarm at the 

 first, or distant, approach of danger. One hears it taken up here and 

 there all over a large meadow when it is first entered. Then there is a 

 single shrill chirp of somewhat lower pitch, uttered now and then by 

 either old or young. At times one will hear scarcely a note for many 

 minutes, even when many of the squirrels are in sight, and then again 

 the calls will be given back and forth from all sides. 



One old female watched from a distance of 20 feet stood stock still 

 for several minutes at the mouth of her burrow, in upright, "picket- 

 pin" fashion. The fore feet she held against her stomach in front. 

 When she gave the several syllabled call she opened her mouth very 

 wide, depressing the tongue on to the floor of her mouth so that it could 

 not be seen, and uttered the successive notes with much appearance of 

 effort. The convulsive movements of the body were synchronous with 

 the notes as uttered. The picket-pin attitude is really not so frequent 

 as a crouching one, though when it is assumed it renders the squirrel 

 visible a long way, especially where the grass is short. When feeding, 

 the squirrel hunches over on its haunches, and uses both front feet and 

 the fingers of these for holding and manipulating the food. When 

 foraging the squirrels do much slinking along, with body horizontal and 

 seemingly touching the ground. When a general alarm is sounded one 

 sees them running in every direction, with a rather clumsy and not 

 rapid, hopping gait. When so running the tail, short and never con- 

 spicuous, is held either out straight behind or raised at an angle 

 of 30 degrees. Often when halting, or coming to a stand on the alert, 

 the tail is twitched up from the horizontal several times in rapid 

 succession, the whole body also twitching at the same time. 



Rarely does an Oregon Ground Squirrel leave the ground, even to 

 climb onto a rock or log. The body is relatively heavy and the general 

 movements are far from nimble. In just one instance was a squirrel 

 observed to have actually climbed; one individual was seen at Sugar 

 Hill, Modoc County, up in a bush four feet above the ground (W. P. 

 Taylor, MS). Marshes or very wet meadows are avoided; in other 

 words, this species does not take to water. Still, we have the one 

 instance of an individual, near Oanby, Modoc County, seen (W. C. 

 Jacobsen, MS) swimming across the Pit River. The current here was 

 sluggish and the channel about eighteen feet wide. The act was to 'all 

 appearances voluntary. 



At the season of our special observations, the middle of May, the 

 Oregon Ground Squirrels were seen to be feeding on practically every 

 sort of pasture vegetation. Cuttings of meadow grass, blades and stems 

 of grain, and leaves and stems of alfalfa were seen on their mounds or 

 in the mouths of their burrows. As already stated, determination of 



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