THE NORTH-AMERICAN JUMPING MICE. 
J. A. ALLEN. 
THE jumping mice of North America form a peculiar group, 
restricted, with one exception, so far as now known, to the 
middle and northern parts of North America, ranging from 
North Carolina, Missouri, New Mexico, and central California, 
northward to Labrador, Great Slave Lake, and the Yukon River. 
They are a little larger than the common house mouse, with 
very long hind legs and a very long tail. They are yellowish 
brown above and white below, the color of the dorsal and ven- 
tral areas being sharply separated by a broad lateral line of bright 
yellowish orange. They generally prefer moist meadows, marshy 
thickets, and the edge of woodland, but some species frequent 
deep forests, near streams. They are thus necessarily local in 
distribution, and not generally abundant, and being apparently 
nocturnal in habits are not often met with. They also pass the 
severer parts of the winter in hibernation. Opinion seems to be 
divided in reference to whether they constitute a distinct family 
type, or merely form a well-marked subfamily of the Old World 
Dipodidz, or Jerboas, with which they were formerly associated 
generically by early writers, and of which they may be consid- 
ered the American representatives. They were first generically 
separated from the Old World Jerboas by Coues in 1875, under 
the name Zapus, which he considered to represent also a dis- 
tinct family, Zapodide. 
The members of this genus greatly resemble each other in 
size and color; so much so that, with the scanty and imperfect 
material then available for study, Baird, in 1857, and Coues, 
in 1877, recognized only a single species. A second was made 
known by Miller in 1891, and a third by Allen in 1893, while 
during the following six years some twenty additional species 
and subspecies were added. Mr. Edward A. Preble, assistant 
in the United States Biological Survey, has recently made a 
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