They were free to go, but Harkness paused at a renewed screaming from the jungle. Again the hairy ones poured forth into the open glade. He had half raised his bow, with arrow ready, before he saw that this was no attack. The screams merged discordantly with other sounds--a crashing of uprooted trees--a chorus of harsh coughing--snorting--unrecognizable noises. And the people were cowering in terror. They half-ran toward the safety of their caves, but the throwers of thunder, the demons on the lava bed, were between them and their homes. They turned to face the jungle, and the wild sounds and crash of splintered wood that drew near. Harkness saw the first head that appeared. He stared in open-mouthed amazement at the armored monster. Thick plates of shell covered its mammoth body and lapped part way over the head to end at beady, wicked, red eyes on either side of a single curved horn. An instant the animal waited, to glare at the cowering human forms it had tracked to their lair; others crashed through beside it; and in that instant Harkness recognized the huddled group below as brothers. Far down they were, in the long, weary path that was evolution, and hardly come as yet to a consciousness of self--but there were those who leaped before the others, their long spears couched and ready; they were defending the weaker ones at their backs; they were men! And Harkness was shouting as he raised his crude bow. "Shoot!" he ordered. "Kill the brutes!" His own arrow was speeding true. The rush of mammoth beasts was on as he fired, but it was checked as quickly as it began. An inferno of explosions rose about the rushing bodies; crashing detonations struck two of them down, their heads torn and crushed. Between the helpless, primordial men and the charging beasts was a geyser of spouting earth and rocks, through which showed ugly heads and tremendous bodies that wheeled and crashed madly back into the jungle growth. Harkness suddenly realized that only he and Chet had fired. Diane's bow was on the ground. He saw the girl beside it, sitting upright; but her body was trembling and weaving, and she was plainly maintaining her upright posture only by the greatest effort. * * * * * He was beside her in an instant. "What is it?" he demanded. "Are you hurt? What is it?" She raised her hand that he might see; her lips, seemed almost too numb for speech. "Only a scratch," she whispered, but Harkness saw her eyes glazing. He dropped to his knees and caught her swaying body in his arms. "A scratch," she repeated in a fading voice, "from the spear.... Poison ... I think." A head appeared over the lava crest. Harkness saw it vaguely. He knew that Chet had the newcomer covered; his bow was drawn. It meant nothing to him, for Diane was wounded--dying! Dying, now, in his arms....