THE POLAR BEAR. 243 perate in self-defense, but it is seldom that they become the aggressor. The brain of the bear is very highly developed, and they soon learn all kinds of accomplishments. The lion is an uncouth boor in comparison. The Polar Bear, Zhalassarctos Maritt- mus, is the only representative of the ge- nus. He is an almost wholly carnivorous animal, his food consisting of fishes and seals, which he skillfully captures. He can swim better than any other bear, and has been known to swim a strait forty miles wide. The fur is silver white tinged with yellow. This color is variable in specimens, and according to the seasons. The head is much smaller than that of the grizzly or black bear, and is ferret-like, with a decided downward curve to the nose. The nose does not possess the flexibility of that of the rest of the bear family, although the polar bear has the higher development of the sense of smell. Johnson says that the flesh is good to eat, but other writers do not agree with him. Kane was poisoned by