Time and again he halted at the sight of some gnarled tree trunk which more or less resembled a Formian. He went slowly and cautiously, frequently stopping to listen and look about him, but not a sound nor a radiation did he hear, not a sign of life did he see. Reassured somewhat now, he was beginning to push on a little more boldly, when he was startled as he saw an ant man standing motionless beside a tree not far ahead. There could be no mistake about it this time. This was no stump, nor was it a twisted branch; and, as if to convince him, just then the Formian changed its position slightly. It was holding a rifle, and was very evidently on guard, keeping a careful watch of the woods about it. Cabot had stopped short just as soon as he had caught a glimpse of the ant man, and a moment’s observation convinced him that he himself had not yet been seen. So with great caution he began to back away. If only he could gain the shelter of a tartan bush close at hand, he would be safe. Cabot could not remove his gaze from the Formian before him; and, though he kept moving away, every moment he was in an agony of fear lest the other should turn and look in his direction. Of course Myles was armed. A shot from his revolver would not be perceived by the antennae-sense which takes the place of hearing among the native inhabitants of Poros. But what he feared was that his enemy would radiate for help before the fatal bullet could do its work. Accordingly it would pay to try to get away by stealth. He had taken several backward steps, and the Formian had not yet seen him. He was beginning to hope that he could withdraw in safety now. He could feel, rather than see, that he had almost gained the shelter he was seeking, when suddenly the ant man turned about and looked straight at him. The Formian was not more than two parastads away, and for a moment his surprise was as great as that of Cabot had been. But it lasted only for an instant, and then he raised his rifle to his shoulder and fired. Quick as he was, however, Myles had been quicker, and the moment he saw the movement on the part of the Formian, he discharged his own revolver, and then turned and bounded into the forest. He heard the other’s bullet as it exploded in a tree near him, and also the loud radiations of the ant man, mingled with the explosion of his own bullet. * * * * * Cabot ran now at full speed, caring little in which direction he went, intent on escape from the immediate danger which had confronted him. Running swiftly though he was, he was able to hear the call of the Formian answered. A radiation that seemed to be far away, replied; and Cabot could not determine from which direction it came. He had no time, however to stop and wait. His very life, and the destinies of a planet, might depend upon his speed. So he ran swiftly on.