All about the pitfall the earth was plowed in furrows and beaten down by the feet of some monstrous animal. Evidently the calf was in the company of its mother when it fell a victim to the art of the pitfall diggers. It was plain that the mother had spent most of the night about her young in a vain effort to release it. Well did the cave boys understand the signs, and, after their first wild outburst of joy over the capture, a sense of the delicacy, not to say danger, of their situation came upon them. It was not well to interfere with the family affairs of the rhinoceros. Where had the mother gone? They looked about, but could see nothing to justify their fears. Only for a moment, though, did their sense of safety last; hardly had the echo of their shouting come back from the hillside than there was a splashing and rasping of bushes in the swamp and the rush of some huge animal toward the little ascent leading to the valley proper. There needed no word from either boy; the frightened couple bounded to the tree of refuge and had barely begun clambering up its trunk than there rose to view, mad with rage and charging viciously, the mother of the calf rhinoceros. CHAPTER VIII. SABRE-TOOTH AND RHINOCEROS. The rhinoceros of the Stone Age was a monstrous creature, an animal varying in many respects from either species of the animal of the present day, though perhaps somewhat closely allied to the huge double-horned and now nearly extinct white rhinoceros of southern Africa. But the brute of the prehistoric age was a beast of greater size, and its skin, instead of being bare, was densely covered with a dingy colored, crinkly hair, almost a wool. It was something to be dreaded by most creatures even in this time of great, fierce animals. It turned aside for nothing; it was the personification of courage and senseless ferocity when aroused. Rarely seeking a conflict, it avoided none. The huge mammoth, a more peaceful pachyderm, would ordinarily hesitate before barring its path, while even the cave tiger, fiercest and most dreaded of the carnivora of the time, though it might prey upon the young rhinoceros when opportunity occurred, never voluntarily attacked the full-grown animal. From that almost impervious shield of leather hide, an inch or more in thickness, protected further by the woolly covering, even the terrible strokes of the tiger's claws glanced off with but a trifling rending, while one single lucky upward heave of the twin horns upon the great snout would pierce and rend, as if it were a trifling obstacle, the body of any animal existing. The lifting power of that prodigious neck was something almost beyond conception. It was an awful engine of death when its opportunity chanced to come. On the other hand, the rhinoceros of this ancient world had but a limited range of vision, and was as dull-witted and dangerously impulsive as its African prototype of today.