art of the county.
Along the small streams in this district were extensive marshes which
were evidently old beaver meadows. About the edges of the marshes were
fringes of tamaracks.

At the beginning of the nineteenth century Washtenaw County was an
unbroken wilderness, and deer, wolves, bear, and other large and small
fur-bearing animals were abundant. A few white trappers were in the
region, and the Indians frequently passed through on the old Tecumseh
Trail to Detroit, where they went to trade.

In 1809 three Frenchmen established a trading-post at Ypsilanti, where
the Tecumseh Trail crossed the Huron River, and for several years they
traded here with the Indians. In 1823 the first permanent settlement in
the county was made by Benjamin Woodruff and two others at Woodruff's
Grove, not far from the present site of Ypsilanti. A settlement was made
at Ann Arbor in 1824, and many pioneers arrived in the county during the
next few years.

With the coming of the settlers and the clearing of the forests the
natural mammal habitats were greatly altered or destroyed. This,
together with the hunting by the settlers, caused the gradual
disappearance of the larger mammals, such as the cougar, bear, wolf,
lynx, and deer. The clearings of the settlers created new habitats which
were gradually occupied by species better adapted to civilization, such
as the mole, woodchuck, ground squirrel, fox squirrel, and skunk, and
also the house mouse and Norway rat, which were brought in
unintentionally by the settlers.

For sixty-five years I have lived almost constantly in Washtenaw County
and I have seen the latter part of the exploitation of the forests of
the county and the extermination of most of the larger mammals. From my
father, who settled in the county in 1836, and other old pioneers I have
drawn extensively for information about the early mammals of the county.
Much use has also been made of information contained in the Michigan
Historical Collections. The specimens on which the records here are
based are mostly preserved in the Museum of Zoology.

For considerable assistance in the preparation of the manuscript of this
paper I am indebted to L. R. Dice, Curator of Mammals in the Museum of
Zoology, University of Michigan.

LIST OF SPECIES

_Didelphis virginiana virginiana._ Virginia Opossum.--This species is
rare in the county. One was taken by my father, Jessup S. Wood, in 1845,
in Lodi Township. We have later records