FIELD BOOK OF MAMMALS 



throughout Hudsonian Zone in eastern Canada; Hmits of 

 range unknown." (Preble) 

 Jackson Jumping Mouse. — Napceozapus insignis frutectanus 

 Jackson. 

 Resembling typical insignis in size but differing in color. 

 Sides clay color sparingly mixed with black; dorsal band 

 clay color with heayy mixture of black; ears edged with 

 pinkish buff; nose and face dusky; tail bicolor, olive-brown 

 and white, white tip nearly an inch long; underparts 

 creamy white. Total length, 9.4 inches; tail vertebrae, 

 5.8 inches; hind foot, 1.24 inches. Found in Oneida and 

 Oconto Counties, Wisconsin, 



The Jumping Mouse is readily recognized by its long slender 

 tail and tawny or ochraceous color. The only other rodents 

 with such leaping modifications, namely, long hind legs and 

 elongate tail, are the Pocket Rats which, as their name im- 

 plies, may be known by their external cheek-pockets. In 

 addition, these latter rodents are much larger and of such 

 different structural and color characters that they should 

 never be confused with Jumping Mice. 



Jumping Mice are peculiar in several ways. They are 

 erratic in distribution, more often rare than common and yet 

 in some localities being encountered as fairly abundant. They 

 hibernate (Plate XXXII.) during cold weather and prepare 

 for this dormant period by putting on a heavy layer of fat. 

 These Mice show a fondness for meadows and grassy spots, 

 and may be started in the daytime when they leap away from 

 a threatening foot step. The genus is distributed in forested 

 sections and on the less arid plains, although it seems to be 

 restricted to the brush and forest-bordered streams in the 

 latter instance. 



In structure the Jumping Mice are set far apart from the 

 common rodents, the cricetines, and occupy a family position 

 next to the Porcupines. The genus Zapus is restricted to 

 North America, but Napceozapus is found in Asia as well. 



The number of young is five or six and but one litter is 

 raised in a season. 



Family Erethizontidae. American Porcupines 



Large, robust rodents having quills 01 spines in their pelage, 

 the spines loosely attached to the skin; toes four in front, five 



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