422 CHAPTERS ON THE NATURAL HISTORY 



cies of the only genus of the family Zapodidce of the order Ro- 

 dentia. This interesting little animal measures from tip to tip, 

 when adult, between seven and eight inches, the tail being con- 

 siderably longer than the body. It is white on its lower parts, 

 while on the back and superior aspects it is of a reddish brown. 

 Ranging over North America generally, although nowhere abun- 

 dant, it is known in some localities as the Canada jerboa, it hav- 

 ing much the appearance of one of those animals, with its long 

 hind and short forelegs, and its power of taking long leaps. Mr. 

 Abbott, in comparing the habits of hibernation of the Deer mouse 

 (P. leucopus) with Zapus, says: "These two mice, popularly so 

 called, hibernate with regularity in one sense, but dift'er inter sc 

 in another. The former (Zapus) once torpid, remains so until 

 spring, a few warm days in winter failing to rouse them; but 

 the White-footed mouse seems simply to sleep soundly rather 

 than grow torpid, and responds with considerable prompt- 

 ness to any disturbance. The Jumping mouse builds a nest 

 of leaves and grass at a comfortable depth from the 

 surface of the ground (not a " ball of mud,' as stated in the Ency- 

 clopedia Britannica, Art. ' Jerboa '), and, once fairly settled 

 therein, is beyond the various sudden changes of our winters; the 

 White-footed mouse, on the contrary, utilizes an old bird's nest, 

 or has a nesting place beneath a log or in a half-decayed stump. 

 In such positions, of course, the occupant is more likely to be dis- 

 turbed, and is also directly exposed to the varying temperature. 

 Is it to meet the requirements of his condition that this mouse 

 lays up a goodly stock of food during the autumn? Something 

 the jerboa, or jumping mouse, does not do. However this may 

 be, the fact remains, that both these rodents are quite sensitive 

 to cold, and hibernate as soon as the winter sets in ; yet how dif- 

 ferently is this faculty exercised! " 



Zapus may have several litters during a summer, and the fe- 

 male bring forth from three to four each time. Sometimes the 

 mother may be seen dragging her semi-hairless progeny along, 

 bumping them over the ground as they hang on like grim death 

 to her teats. This animal in leaping takes a course in zigzags, 

 clearing two or three yards at a time, springing with its hind feet, 

 but landing on its fore feet at each bound. Farmers sometimes 

 plow it up in their wheat fields, when it makes off in magnificent 

 leaps. It feeds on grain and various kinds of seeds, but rarely 

 does much damage. Strictly nocturnal in its habits, it may be 



