short range. These "husking places" are conspicuously marked by the hulls of seeds and by the rinds and pits of cultivated or wild fruits. Examination of these "kitchen middens" will sometimes give a pretty accurate idea of the character of the squirrels' rations in any locality. A great many of the matured seeds, however, are carried directly below ground to the permanent storehouse.
Droppings, or feces, of the Ground Squirrel are to be observed widely scattered rather than deposited in piles. They may be found about the "husking places" or along the trails or paths which lead from the burrow to the feeding grounds. In the burrows they are accumulated in special places evidently set aside for the purpose. The feces are generally of a cylindrical shape, rounded at the ends, but are quite variable in diameter and volume. In April when green food is abundant fresh feces are of a greenish hue and are often soft and flattened. During the drier portions of the year the droppings are covered with a dark brown coating, while the interior is composed of a dry mass consisting of hulls of weed seeds and finely chopped and shredded vegetable fiber, from 3 to 10 millimeters long. A typical dry dropping measured 16 millimeters (⅝ inch) in length, with a diameter of 6 millimeters (¼ inch), and weighed 1⁄10 of a gram.
The California Ground Squirrels do not dwell in thickly populated "colonies" of sharply restricted extent, as is the case with the prairie dogs of the Middle West. Still there is with our rodent a tendency to occupy certain definite tracts in a general territory to the exclusion of intervening places and this without obvious reason as regards food
Fig. 6. Plot (plan and elevation) of used burrow of a male "digger" squirrel, as excavated by J. Dixon on an alluvial talus in the foothills near San Emigdio, Kern County, April 28, 1918.
Main entrance at a; refuse sump in old nest-cavity at b; "blind" exit in thick grass at c. Unusual depth of burrow, as shown in profile, was due to thick rock-filled overlying stratum, beneath which the squirrel had found easy digging horizontally after having once penetrated the less resistant part of the layer at the edge of the talus.
Total length of burrow, 34 feet; average diameter, 4½ inches; greatest depth reached, 5½ feet; volumetric contents of entire burrow, 44⁄5 cubic feet.
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