In many places the soft, moist earth in the woods is riddled with little pits dug by these squirrels apparently when they are after larvæ or perhaps edible roots. Throughout the summer, but especially during the last half of the season, and in autumn Douglas squirrels work with persistent energy to amass great stores of seed-bearing cones, which they heap, sometimes bushels of them, about the bases of trees, stumps, and the upturned roots of fallen trees or under other shelter. Cones are also buried here and there in the loose leaves and humus. In winter many holes in the snow with piles of cone scales at the entrances show where the owners have dug down to their stores. [Illustration: HOG-NOSED SKUNK _Conepatus mesoleucus_] [Illustration: NINE-BANDED ARMADILLO _Dasypus novemcincta_] Some of their nests are constructed in hollow trees, many others on branches near their junction with the trunks, and still others in underground dens under roots, logs, or stumps. In winter when alarmed these squirrels sometimes race down the tree trunks and take refuge in holes leading through the snow to their food caches and underground burrows. The nests built in tree-tops are usually rather bulky, measuring a foot or more in diameter, and are made of small twigs, dry leaves, moss, grass, and fibrous bark. They are commonly lined with such soft material as feathers and fur. The young, numbering three to seven at a litter, are born at any time between April and October. The extraordinary intelligence and sense of prevision possessed by squirrels of this group is well illustrated by certain local food migrations. These have been observed in eastern Oregon in years when the cone crop has failed and nothing was available to lay up for winter. Under such conditions to remain in the mountain forests would mean death by starvation before winter had fairly begun. In 1910 and 1913 failure of the cone crop occurred in eastern Oregon and these squirrels promptly left the mountain forests in September and descended along creek courses to the open sagebrush plains as much as seven or more miles from the border of their ordinary haunts. In this open country they wintered successfully, raiding the farmers’ grain bins, root cellars, and other stores, and otherwise showing their supreme fitness to survive in the struggle for existence. With the coming again of summer they promptly returned to their abandoned homes in the pines. It appears to be one of the marvels of animal intelligence that under such circumstances as those named above the entire body of the squirrels on the mountains should have known what to do, especially as a great percentage of their number could never have had any previous experience as a guide. =THE GRAY SQUIRREL= (=Sciurus carolinensis= and its relatives) (_For illustration, see page 547_)