136 
MAMMALIA. 
and is fond of corn and several kinds of grain. It also eats the 
larvae of certain insects. In this region the beechnut constitutes 
its staple commodity, as it does that of all our squirrels, and 
since this nut is produced in large quantity each alternate year, 
we are able to predict with considerable certainty the periods 
when the Chipmunk will be abundant. For wherever, in autumn, 
this animal finds a sufficient supply of nuts he is sure to remain 
until the following summer. Here, in beechnut years, the fore- 
runners of the great migration arrive in September, and by the 
first week in October the woods literally swarm with them. Find- 
ing an abundance of food they immediately establish themselves 
for the winter, and begin at once to hoard up large stores. They 
are the least hardy of our squirrels, commonly going into winter 
quarters before the middle of November, and rarely appearing 
again in any numbers till the warm sun, in March or April, has 
caused plots of bare ground to appear between the snow-banks. 
Early thaws sometimes bring them out in February ; and after 
having once emerged, they often make little excursions over the 
snow during pleasant days, though the temperature may be several 
degrees below freezing. In running from tree to tree, even when 
not pursued, the length of their bound varies from twenty-five to 
thirty-four inches (635 to 863 mm.), a long leap for so small an 
animal. The season of spring is occupied with the duties of rear- 
ing the young, which, before June, are old enough to leave the nest. 
At this time the species attains its maximum in numbers, the 
young and old together inhabiting all parts of the woodland. Fore- 
seeing that the nut crop will fail (this being the even year), they 
commonly emigrate in July and do not again appear till September 
or October of the ensuing year. 
Briefly, then (leaving out of consideration the small number 
of resident individuals, and the migrants that sometimes pass 
through on their way to distant- parts), we find that Chipmunks 
reach the Adirondack region during September or October of the 
