Although one of the most distinctive animals of the sagebrush plains, this chipmunk also ranges into the borders of open forests on the mountain sides. It is most numerous on flats and foothill slopes among heavy growths of sage and rabbit brush. When its territory is invaded by settlers it does not hesitate to gather about the borders of fields and even to raid barns in search of grain and other food. Its burrows are dug under large sagebrush and other bushes and under rocks and similar shelter. As with others of their kind, painted chipmunks habitually gather seeds of many plants and carry them in their cheek pouches to their underground dens. In addition to seeds and green vegetation, they eat any fruits growing in their haunts, and also many insects, especially grasshoppers and larvae. In one locality in Nevada during June and July more than half their food consisted of a web worm and its chrysalids with which the sage bushes swarmed. The chipmunks climbed into the bushes and pulled the larvæ from the webs. As half the bushes were infested, the work of the many chipmunks had a material effect in reducing the numbers of this pest. The vegetable food eaten includes the seeds of _Ribes_, _Kuntzia_, _Sarcobatus_, pigweed, and many other weeds, serviceberry, various grasses, oats, wheat, and the seeds of small cactuses. They regularly climb into the tops of large sage and other bushes for their seeds and the ground beneath is often covered with the small sections of twigs cut by them. They climb readily and often travel from bush to bush through tall thickets like squirrels in tree-tops. On warm mornings after frosty nights they may be seen in the tops of the bushes basking in the sun. Throughout most of their range they begin hibernation in September or October, and reappear early in spring. The young appear a month or more later, and litters containing from two to six may be born throughout the summer, indicating the possibility that several litters may be born to the same pair in a season. So alert and shy are they that even a person in their haunts day after day will see but few of them. Their hearing is extremely acute, and even at a great distance the footsteps of an intruder sets them all on the alert. On every side they run swiftly to cover before the observer has opportunity to see them. In such places a large setting of baited traps will reveal their presence in surprising numbers. In one locality, during a brief visit, traps set among the brush for other small mammals yielded more than forty chipmunks.