Not a sound had Seymour heard but the wolf cries, yet his friend had been snatched almost from under his nose, and that without the baronet catching even a glimpse of his abductors. “It’s maddening!” he burst forth at length. “Something must have carried him off. He cannot have disappeared into thin air! I’ll fetch Silas, and between the pair of us we may pick up some sort of a trail.” So ruminating, with his mind still exercised with the baffling problem, he turned, climbed the ridge, and retraced his steps through the jungle. Suddenly he stopped, thinking he heard a footstep behind him; but nothing could he see moving, and, telling himself that the disappearance of his friend had shaken his nerve and made him fanciful, he pressed on once more. Three minutes later he pulled up again, and this time he knew there was no mistake. Something was dogging his steps, moving when he moved, and stopping when he came to a halt! For an instant a wild, unreasoning fear swept over him, urging him to break into a run, but, with an exclamation of disgust at his own weakness, he shook it off, and moved forward again, cool, determined, and watchful. But once more behind him came those ghostly footsteps. Roused to a fury by the grim persistency of the thing which was tracking him, Seymour faced round with a jerk, and fired point-blank into the fungi behind him. As the report of the rifle rang out, a fearful death-scream awoke the echoes of the underworld, a scream so full of diabolical rage and impotent fury that the usually iron-nerved baronet trembled like a child as he heard it. Controlling his agitation with some difficulty, he moved cautiously towards the spot whence the cry had come; but, though he searched long and well, he could see no sign of the creature he had shot, save in one place, where the green of the moss was disfigured by a dark, red stain. At length he moved on again, with that fearful cry still ringing through his ears, and his heart throbbing madly with a nameless fear. What creature was it, he wondered, that could give voice to a cry like that? What animal could it be that tracked him with such devilish cunning? Doubtless when he discovered that, he would have found the key to the mysterious fate of the inventor. He shuddered still at the mere thought of the cry. Then, of a sudden, his heart seemed to stand still. Behind him, tireless as ever, came the pad-pad of feet upon the moss! So there were more than one of these creatures, and they meant to track him down to the end. A cold sweat broke out upon Seymour. If he could only see the Thing which menaced him; if he but knew the extent, the nature of his danger! Against visible foes he would have fought with the bull-dog courage which was his chief characteristic, but against the phantom inhabitants of this land of shadows he was helpless.