18 INTRODUCTION. 
spring all leave us in the autumn there would be no 
birdless interim; and this applies to the whole coun- 
try. There is everywhere a complement of resident 
birds, and in autumn, too, there comes from the north 
a goodly supply of those birds that live the greater 
part of the year in the far north, but find the winters 
there too severe. This migratory flight is one of 
considerable irregularity, and often a wide extent of 
territory is visited for some years, every winter, by 
large numbers of northern birds, and then a year or 
two will pass and not a specimen be seen. It is a 
popular fancy that the appearance in unusual numbers 
of birds belonging to the Canadian fauna in the Mid- 
dle United States portends a severe winter; but this 
is true only in a limited sense, if true at all. There 
may be severity of weather in the region forsaken, 
but not necessarily in the one visited. It is probably 
wholly a matter of food, and we can readily see that 
some freak in the summer weather may lessen the 
supply of this. Certain it is that little birds, like 
little boys, do not like to go hungry, and to carry 
the simile still further, there is practically no limit to 
their powers of consumption. Just as I have often 
eaten—in years gone by—until I could scarcely 
walk, so I have found birds so full that it was with 
much difficulty that they could fly. This has been 
seen in the case of robins, reed-birds, and cedar- 
birds. I remember, too, a lovely little chipping spar- 
row that lived in my yard, and which became quite 
tame. We fed it on crumbs until it became round as 
a ball, and when hopping on the path you could not 
see its feet. 
