Page:Popular Science Monthly Volume 84.djvu/152

148 well known, their hibernation presents many less well-known and peculiar features.

In the first place, bears are the largest animals known to hibernate, and the only members of the great order Feræ, or flesh eaters, that do so. However, all the species of bears do not hibernate. Some that inhabit tropical Asia are active at all seasons and, according to the testimony of many articarctic [sic] explorers, the polar bear is also.

Grizzly and black bears in the United States generally remain active until after snow has fallen and severe weather has begun, that is to say, until the end of November or later. There seems to be a great individual difference in this regard, however, and there are records of bears being seen in all months of the year. Whether those that are abroad in midwinter have been disturbed in their winter sleep or have never gone into winter quarters, I am unable to say.

In some parts of the country there was a belief among the pioneers that bruin swallowed a knot of wood before entering upon his long fast, the purpose being to nourish him or "to keep his stomach from shrinking." How this absurd notion arose, I can not conjecture. The bears, like most other animals, become very fat in autumn when food is plentiful, and the fat is gradually resorbed by the blood and carried wherever it is needed in the body. The animal requires much less food while dormant than when active and there is nothing especially mysterious or unusual about its nutrition during this period. Neither is there any more reason why its stomach should "shrink" than that ours should shrink when we occasionally abstain from eating on account of sickness or any other reason.

The most remarkable fact in connection with the hibernation of the bears is the birth of the young during this period. With the black bear this occurs in January or February and the mother remains in her den for six weeks or two months longer. The young are generally two in number, sometimes one and sometimes three. It must be a tremendous drain upon the vital resources of the mother to nourish her offspring at the conclusion of this long fast and she would be wholly unable to stand it if it were not for the small size of the young which weigh only a few ounces at birth and find an ample resting place upon the palm of a man's hand.

This animal is better known in some parts of the country as the "ground hog." Its appearance is familiar to most people, but it is not so generally known that this clumsy, short-legged, short-tailed inhabitant of underground burrows is a member of the squirrel family, as is the prairie dog of the western plains.