A few weeks before Kazan had looked upon a similar scene when he had returned into the north from Broken Tooth's old home. It had not interested him then. But a quick and thrilling change swept through him now. The beavers had ceased to be mere water animals, uneatable and with an odor that displeased him. They were invaders--and enemies. His fangs bared silently. His crest stiffened like the hair of a brush, and the muscles of his forelegs and shoulders stood out like whipcords. Not a sound came from him as he rushed down upon Broken Tooth. The old beaver was oblivious of danger until Kazan was within twenty feet of him. Naturally slow of movement on land, he stood for an instant stupefied. Then he swung down from the tree as Kazan leaped upon him. Over and over they rolled to the edge of the bank, carried on by the dog's momentum. In another moment the thick heavy body of the beaver had slipped like oil from under Kazan and Broken Tooth was safe in his element, two holes bitten clean through his fleshy tail. Baffled in his effort to get a death-hold on Broken Tooth, Kazan swung like a flash to the right. The young beavers had not moved. Astonished and frightened at what they had seen, they stood as if stupefied. Not until they saw Kazan tearing toward them did they awaken to action. Three of them reached the water. The fourth and fifth--baby beavers not more than three months old--were too late. With a single snap of his jaw Kazan broke the hack of one. The other he pinned down by the throat and shook as a terrier shakes a rat. When Gray Wolf trotted down to him both of the little beavers were dead. She sniffed at their soft little bodies and whined. Perhaps the baby creatures reminded her of runaway Ba-ree, her own baby, for there was a note of longing in her whine as she nosed them. It was the mother whine.