As he looked inquiringly ahead now, he observed a huge American cougar, larger than that of the night before, issuing from among the branches. With his phosphorescent eyes fixed upon the terrified lad, he was stealing slowly along the log, giving utterance to a deep guttural growl, separating his lips as he did so, so as to show his long, white, needle-like teeth, intended for the rending of flesh. For a moment Fred was transfixed at the sight. The cougar clearly meant fight, and assumed the offensive without a second's hesitancy. He seemed to have been crouching in the bushes, and calmly awaited the time when the boy should advance too far to retreat. “I guess I'd better go back!” exclaimed the latter, recovering himself, and beginning his retrograde movement; but a few hitches showed that he could not escape the cougar in this fashion, if he really meant business, and it looked very much as if he did. The beast had already left the other side, and, like his intended victim, was supported over the chasm by the tree. He had advanced beyond the fork made by the junction of the lowermost branches with the main stem, and was stealing along with an appearance of excessive caution, but really with the certainty of a brute who feels that there is no escape for his prey. He moved slowly, burying his long, sharp claws so deeply in the bark at each step, that his feet seemed to stick as he lifted them again. All the time his large, round eyes, which had a greenish glare like those of a cat, were never removed from the face of the lad, and the guttural growl that came from the lowermost depths of his chest was like the muttering of distant thunder. It was not until about a dozen feet separated the two that Fred recalled that his case was not so desperate as he had imagined. He held a loaded rifle at his command, and the distance was too short for any mistake to be made in the aim. “I guess I'll stop _your_ fun!” was the exultant exclamation of the lad, as he brought his rifle to his shoulder. “I don't like to throw away a shot on you, but I don't see how it can be helped.” He sighted directly between the eyes. His hand shook a little, and the weapon was heavy, but it was impossible that he should miss. The cougar continued his slow, cautious advance, apparently unaware or uncaring for the deadly weapon aimed at him. The distance was very slight between the two when the trigger was pulled, and the heavy bullet, tearing its way through bone and muscle, buried itself in the brain, extinguishing life with the suddenness almost of the lightning stroke. The guttural growl wound up with something like a hoarse yelp, and the cougar made what might be termed his death-leap.