Eleven specimens of this jumping mouse were taken from a relict
population restricted to a shrub-grass habitat adjacent to a small
spring-fed stream and impoundment in Deer Draw (10 mi. S and 5 mi. W
Reva). Similar isolated populations may be present in the few other
suitable mesic habitats in Harding County, but we have trapped
extensively, yet unsuccessfully, for _Zapus_ in such situations;
specimens are known, however, from the Long Pine Hills and from along
the Little Missouri River in adjacent Carter County, Montana. It is of
interest that a relict population of _Peromyscus leucopus_ also occurs
in Deer Draw.
The testes of two adult males obtained on June 3 measured 7, whereas
those of one taken on May 16 measured 16. Seven embryos (measuring 8 in
crown-rump length) were carried by a molting female trapped on June 16.
Our specimens of _Zapus_, currently under study by Paul B. Robertson,
appear to be intergrades between the subspecies _campestris_ and
_intermedius_, but resemble the former more closely than the latter.
~Erethizon dorsatum bruneri~ Swenk, 1916