He has extraordinary strength. I have known him to drag the carcass of a cow or a steer of twice his own weight. In several instances this was dragged up the mountain-side over fallen logs, yet it was apparently moved without extraordinary effort. The grizzly is exceptionally expert and agile with his paws. With either fore paw he can strike like a sledge-hammer or lift a heavy weight. He boxes or strikes with lightning-like rapidity. Most grizzlies are right-handed; that is, the right fore paw is most used. If a small object is to be touched or moved, he will daintily use but one claw. The black bear would use the entire paw. The fore-foot prints made by the grizzly are much shorter than the tracks made by his hind feet. His hind foot leaves a track similar to the bare-footed track of a man, while the track of the fore foot has the appearance of the grizzly's having walked upon the front of his foot,--the ball and toes,--with the heel upraised. The fore claws are from two to five inches long, the hind claws much shorter. The fore ankles of the grizzly are smaller than the black bear's, the hind feet relatively larger; the claws are much longer and less curved. The grizzly's claws do not curve as sharply downward as a black's, but the claw-points extend well beyond the ends of the toes. The black's curved claws are much used in climbing; the grizzly's claws are used mostly for digging. The largest grizzly-track that I have measured was slightly more than thirteen inches long, and seven and one half inches wide at the widest point. These measurements did not include the claw-marks. In places where this bear had slipped on snowy or muddy ground the track with claw-marks was of most formidable appearance. Many of the big Alaskan grizzlies have large feet, sometimes making a track eighteen inches in length. However, in the Rocky Mountains I have seen a large track that had been made by a comparatively small bear. More than once I have seen bears weighing less than four hundred pounds whose feet were larger than those of other bears who weighed upwards of six hundred pounds. A large grizzly bear track does not necessarily indicate that it is the track of a large bear. There is marked difference in the ordinary ways of the black and the grizzly. The grizzly is energetic, thorough, works hard, and takes life rather seriously; while the black bear is lazy, careless, does no more work each day than is necessary, and is more playful. The grizzly's hibernating-den is usually a substantial, complete affair, while that of the black bear is more or less of a makeshift. The black bear likes to play with other bears, while the grizzly enjoys playing alone. The black climbs a tree easily and often sleeps in a tree-top; the grizzly bear rarely climbs after he passes cubhood.