--In October, 1883,
George B. Sudworth took one near Ann Arbor. February 13, 1903, E. H.
Frothingham found one under a corn shock about four miles south of Ann
Arbor. In a runway in a small tamarack stand in Steere's Swamp, near the
same place, I trapped an adult female and four nearly grown young,
October 8 and 9, 1903. In February, March, and April, 1921, H. B.
Sherman trapped six in a field containing a little brush, a short
distance south of Ann Arbor. A number of their remains were found by J.
Van Tyne in the winters of 1921 and 1922 near Ann Arbor, in pellets of
the long-eared owl.

_Microtus pennsylvanicus pennsylvanicus._ Pennsylvania Vole.--Was
formerly found in beaver meadows, but with the clearing of the forests
it has extended its range to the fields of grass and grain, and has
become the most numerous of all the mammals of the county. Records are
at hand for Ann Arbor, Pittsfield Township, and Portage Lake.

_Microtus pinetorum scalopsoides._ Pine Vole.--July 15, 1921, A. G.
Ruthven found an adult male in the oak-hickory woods on his grounds near
the outskirts of Ann Arbor.

_Fiber zibethicus zibethicus._ Muskrat.--In spite of persistent
trapping, muskrats are still numerous in the county. Records are at hand
for Ann Arbor, Pittsfield Township, Portage Lake, Saline, and Ypsilanti.

_Rattus norvegicus._ Norway Rat.--This injurious rodent became common
soon after the settlement of the county. Its omnivorous food habits and
adaptability have enabled it to increase greatly.

_Mus musculus musculus._ House Mouse.--The house mouse did not reach
Washtenaw County until several years after the settlement of the
district. It has become a serious pest, not only to household effects
and stored food, but it has taken to the grassy fields and the woods
bordering grain fields, and is commonly found in shocks of corn. The
amount of damage done by it in this county must be very great.

_Zapus hudsonius hudsonius._ Jumping Mouse.--A few occur in the county.
We have records for Ann Arbor, Portage Lake, and Whitmore Lake. In
October, about 1880, in Lodi Township, a female jumped from a shock of
corn that was pulled over, and when caught, after several jumps of two
feet or more, was found to have three small young attached to her teats.

_Erethizon dorsatum dorsatum._ Canada Porcupine.--The first settlers
found porcupines were common in the county. My father killed one in 1855
in Lodi Township, and the last one known in