HABITS AND FACULTIES. J go, 
dwellings, and has in some places become the pest of 
the horticulturist. 
Whether this difference of habitat arises from original 
constitution, or is the consequence of the long continued 
operation of external causes, is a curious subject of in- 
quiry. The preference for the forest over the open 
country exhibited by the native species, even in situa- 
tions where both have been for a long time equally 
accessible to them, seems to indicate that the former 
supposition is correct ; and this opinion is strengthened 
by the disappearance of nearly every species with the 
progress of agriculture. If their habits were not in- 
superable, they might be expected to have been some- 
what modified ere now, and to have become adapted to 
the new physical conditions to which they are subjected. 
That they have not been, suggests the thought, that like 
the aboriginal race of men, and some of the larger 
quadrupeds, they are destined to give way before the 
advance of civilization, and to have their places filled by 
foreign species. On the other hand, there are some 
facts which tend to show that accidental causes may 
have produced a slow and gradual revolution in the 
habits of the European species, corresponding with the 
changes which, within the historical period, have taken 
place over the surface of the greater part of Europe ; 
and that in process of time, the same influences will pro- 
duce similar results on the habits of the North Amer- 
ican species. All those parts of Europe which are now 
the most populous were covered with forests, at no very 
vol. 7. 49 
