236 NORTH AMERICAN FAUNA [No. 55 



In ordinary travel they go hop, hop, hopping over the ground on 

 the two hind feet or in rapid flight skimming over the surface with 

 tail straight out behind and used as a rudder for keeping their 

 course or making quick and devious turns. 



The use of the long tail always raises a query. It is not powerfully 

 muscular as in the kangaroos but has many uses besides that of an 

 efficient steering apparatus. It balances every motion of the animal 

 and at rest lies partly on the ground. At other times as the animal 

 reaches up for seeds or leaves from plants, the tail serves as a prop 

 or with the two hind feet makes a firm tripod, while the delicate 

 hands reach up for food. In climbing among the branches of tall 

 weeds or sagebrush the animal presses the tail against the stems and 

 steadies itself, and even when sitting on a man's arm or fist one will 

 press its tail down over the side to keep its body in a stable position. 



The long hind feet and heavily muscled thighs are powerful aids 

 to speed and are also used in digging and fighting, while the tiny 

 hands are used with great skill in gathering and holding food and 

 tucking it into the cheek pockets, in making nests, and in loosening 

 up the earth to be kicked far back by the hind feet. Kunning is 

 accomplished entirely on the hind feet, by long leaps, the tracks 

 in the sand often showing 20, 24, and 28 inches from toe to toe. 



The ample, elastic fur-lined cheek pouches, extending back under 

 the skin of the cheeks and sides of neck, when well filled with seeds 

 or grain or rolled oats, hold about a tablespoonful each of food, 

 enough to last the animal for 1 full day and enough to make the 

 storage of an excess food supply a rapid process. They are filled 

 rapidly with the hands and emptied instantly with a single motion 

 of both hands at once, pressing forward from the rear on the 

 outside. 



A little warty gland on the back between the shoulders appears 

 to serve at least two purposes. It has a faint musky odor that may 

 have recognition purposes very useful to the individuals of the 

 species. It also yields an oily substance that may serve as an im- 

 portant hair dressing. If kept in a clean box or cage for a few 

 days the animals become very rough, mussy, and oily in appearance. 

 Given dry sand or dust for a vigorous bath, which they greatly 

 enjoy, they again become sleek and fluffy with removal of excess oili- 

 ness from the fur. 



The animals are so strictly nocturnal that people rarely see them 

 or even know of their presence. Even tame individuals kept in 

 the house would not come out of their nest boxes until long after 

 dark, and all would retire for the day before the first signs of day- 

 light. Still they did not sleep through all of the 15 hours spent in 

 the nest boxes, for they carried in at least their pockets full of 

 food, or more than one load if a supply was available, and ate it dur- 

 ing the day ; they also moved about considerably inside the boxes, 

 and repaired their nests. Behind closed doors in their burrows they 

 apparently do some digging and considerable moving around dur- 

 ing the day, and if a closed door is opened from the outside they 

 usually soon replug it with earth. They see well in the dark and 

 in a moderately lighted room, but sunlight or any bright light 

 causes them to blink and half close their eyes. Their eyes are 

 always closed in sleep, but when awake in a dim light they are 



