MAMMALS OF PENNSYLVANIA AND NEW JERSEY. 109 



Family DIPODID.* ; Jerboas. 



Genus Zapus Coues, Bulletin U. S. Geolog. Surv. of Territories, 2d series, 

 vol. i, p. 253. 



Hudson Bay Zapus, or Meadow Jumping Mouse. Zapus hudsonius 

 ^Zimmermann) . 



1780. Dipus hudsonius Zimmermann, Geogr. Geschichte d. Menschen, 

 'Thiere, vol. 2, p. 358. 



1875. Zapus hudsonius Coues, Bulletin U. S. Geolog. Survey, Territories, 

 2d series, vol. i, p. 253. 



Type locality. Hudson Bay. 



Faunal distribution. Hudsonian, Canadian and Transition zones ; Hudson 

 Bay and Gulf of St. Lawrence to northern N. Jersey, west to northern Rocky 

 Mts. and Great Plains, south in the Alleghanies to North Carolina. 



Distribution in Pa. and N. J. Abundant, locally, in open meadows, 

 swamps and in fields contiguous to water ; rarely entering woodland. Re- 

 stricted in its typical form to the parts of Pa. and N. J. included in the tran- 

 sition and Canadian faunae ; giving place in the upper austral zone to sub- 

 species americanus. 



Records in Pa. and N. J. In the limits of distribution of typical hudson- 

 ius it is so universally, and in many cases, abundantly represented where 

 swampy meadows abound, that it is superfluous to record localities where it 

 has come under observation. 



Habits, etc. Many people who know this elegant creature from chance 

 observation in their outdoor rambles, and easily distinguish it from all other 

 of our so-called " wild mice " by its enormous leaps, long tail and kangaroo- 

 like hind legs and feet, have no acquaintance with its habits. It does not do 

 much leaping in ordinary life, but rather as a quick way of escaping the 

 thousand terrestrial ills to which its humble, every-day life is subject. It is 

 of a most timid nature and ill-fitted to combat tooth and nail with the 

 doughty meadow mice and shrews which infest its feeding grounds. Through 

 the cover of grass and weeds which overarch the hidden mouseways the leap- 

 ing Zapus finds a safe aerial passage from troubles earthy, sentimental and 

 otherwise. In all his jumping that lever-like tail is only a rudder and balan- 

 cing rod ever held at a gentle upward curve, tip-uppermost, frcm the ground, 

 and when flying through the air acting as a trailer and balancer to bring him 

 gracefully to his feet again in good shape for another leap. I can see no dif- 

 ference between this leaping of the long-tailed mouse and that of the tailless 

 spring-frog which haunts the same marshes, except that the frog does not rise 

 so high in the air. Their reasons for jumping are mostly identical. When 



