Often they climb up and scamper over the roof of my cabin; but most of their time on the roof is spent in dressing their fur or enjoying long, warm sun baths. Frequently they mount the roof early in the morning, even before sunrise. I am sometimes awakened at early dawn by a chipmunk mob that is having a lively time upon the roof. In many things they are persistent. Once I closed the hole that one had made in a place where I did not want it. I filled the hole full of earth. Inside of two hours it was reopened. Then I pounded it full of gravel, but this was dug out. I drove a stake into the hole. A new hole was promptly made alongside the stake. I poured this full of water. Presently out came a wet and angry chipmunk. This daily drowning out by water was continued for more than a week before the chipmunk gave it up and opened a hole about thirty feet distant. For eight years I kept track of a chipmunk by my cabin. She lived in a long, crooked underground hole, or tunnel, which must have had a total length of nearly one hundred feet. It extended in a semicircle and could be entered at three or four places through holes that opened upon the surface. Each of these entrance holes was partly concealed in a clump of grass by a cluster of plants or a shrub. I have many times examined the underground works of the chipmunk. Some of these examinations were made by digging, and others I traced as they were exposed in the making of large irrigation ditches. The earth which is dug from these tunnels is ejected from one or more holes, which are closed when the tunnel is completed. Around the entrance holes there is nothing to indicate or to publish their presence; and often they are well concealed. These tunnels are from forty to one hundred feet long, run from two to four feet beneath the surface, and have two or more entrances. Here and there is a niche or pocket in the side of the tunnel. These niches are from a few inches to a foot in diameter and in height. In one or more of these the chipmunk sleeps, and in others is stored his winter food-supply. He uses one of these pockets for a time as a sleeping-place, then changes to another. This change may enable the chipmunk to hold parasites in check. The fact that he has a number of sleeping-places and also that in summer he frequently changes his bedding, indicates that these efforts in sanitation are essential for avoiding parasites and disease. Commonly the bedding is grass, straw, and leaves; but in my yard the chipmunks eagerly seize upon a piece of paper or a handkerchief. I am compelled to keep my eyes open whenever they come into the cabin, for they do not hesitate to seize upon unanswered letters or incomplete manuscripts. In carrying off paper the chipmunk commonly tears off a huge piece, crumples it into a wad, and, with this sticking from his mouth, hurries away to his bedchamber. It is not uncommon to see half a dozen at once in the yard, each going his own way with his clean bed-linen.