Fenner ran after it. He began to pant for breath, and sweat dripped into his eyes. The trail led upstream, now, and soon the stream grew more sluggish and broadened, and the gray trees thinned away. There were dank, twisted plants here, some of them eight or ten feet high, and wide stretches of reeds between which gleamed brown water and patches of oily mud. A chorus of chirps sounded from the marsh, dying away at his approach and starting again when he moved on. Without warning, the needle of the tracker spun round, and Fenner stopped. At the same instant, a lithe form shot out of the reeds towards him. He dodged, throwing himself to the ground. The beast bounded past him, and turned. Fenner rolled over and sat up, groping in the moss for his gun. For a moment they regarded each other, Fenner trying to bring his gun into position. The creature, he saw, had a wedge-shaped face, narrower at the top where the feathery antennae were, wide at the jaw which now gaped showing a double row of small but sharp teeth. Its eyes were round and large, and bulged as a frog's do; they were completely dark purple showing no trace of white. They swiveled forward to stare at him, and as he braced his weapon the beast made a coughing sound and sprang into the reeds. * * * * * All was quiet again. Fenner got up slowly, holding his gun ready, and glanced at his tracker. There was a crack across the face of it, and the needle was motionless. It had struck against a stone, when he fell. He tried to see into the reeds, but he knew it was hopeless. By now, the animal must have changed its color and pattern, and without the tracker to guide him he could distinguish nothing. He commenced to walk upstream, in the hope of somehow flanking it. He unclipped his net capsule and held it ready. It seemed to him that there was a slight movement in the marsh. He stopped. There was no sound about him; the chirpings in the water had ceased, and there was a quality of hush in the air, of almost ominous tenseness as though the marsh itself were waiting for him. He began to feel a little frightened. He looked from side to side. Where was the thing? He had not realized how much he depended on the wrist tracker. He found that he was trembling, and the perspiration stung his eyes so that he had to keep blinking. Cautiously, he slipped one of his gloved hands under the edge of the hood and wiped his eyes. Something rustled slightly in the oil-bushes. These were thick clumps of low shrubs, their branches a naked and repellent pink, covered with spiny leaves on which a thick, pungent oil gathered during each day. It apparently served to attract small insects which the leaves closed over in much the same way as the Venus fly-catcher, of Earth. Fenner went towards the bushes, moving very slowly, his gun tight against his hip, his net-capsule in his left hand.