124 RODENTS OF IOWA 



in nests or burrows, but it is probable that the animal does not 

 use this food since it usually remains quiescent throughout the 

 cold season. 



AVhile the Hudson Bay jumping mouse undoubtedly occurs 

 tiiroughout the state, it seems to be more common in the prairie 

 regions. The few definite locality records which have been ob- 

 tained are as follows — a mounted male specimen (No. 3931) in 

 the Museum of the State University of Iowa was collected at 

 ■Oskaloosa in 1889. The Coe College Museum possesses two mounted 

 specimens, one collected at Britt, August 20, 1911; the other 

 hears no data, although B. H. Bailey assured the writer that 

 it was collected "somewhere" in Iowa. A female spe-cimen of this 

 species collected near Pomeroy was sent in to the University Taxi- 

 dermist's Laboratories, March 20, 1916. The animal had been 

 killed a few days previously. T. C. Stephens of Morningside Col- 

 lege reports three specimens of this form captured near the Iowa 

 Lakeside Laboratory in the summer of 1915. 



PRAIRIE JUMPING MOUSE. 

 Zapus hudsomus campestris Preble. 



Zapiis hudsonius campestris Preble, N. Amer. Fauna, No. 15, 

 20, 1899. 



Description. — Summer: Color above similar to brightly col- 

 ored specimens of the preceding form; dorsal area distinct, suf- 

 fused with ochraceous. buff, the sides ochraceous buff ; under parts 

 and feet white; tail dark gray above, yellowish white below. 

 Fall: Sides yellowish; the dorsal area almost black, the hairs 

 tipped with yellowish ; upper surface of tail darker than in .sum- 

 mer, and ears darker and bordered with whitish. 



Measurements. — Total length, 8.75 inches; tail vertebrae, 5.30 

 inches; hind foot, 1.10 inches. 



This form is very similar to the preceding, differing from it 

 mainly in its slightly larger size, its brighter color, and higher 

 "brain case. The area of intergradation of the two forms includes 

 the western part of Iowa, the present form being distributed from 

 Manitoba south over the Great Plains to Nebraska and west to 

 Colorado and "Wyoming. The prairie jumping mouse is said to 

 replace the Hudson Bay jumping mouse over the northern and 

 more elevated portions of the plains west of Minnesota and Iowa 

 to the base of the Rockv Mountains. 



