Burl blundered up the nearest slope. Sometimes the surface was a hard rind that held him up. Sometimes his feet sank--perhaps inches, perhaps to mid-leg. He scrambled frantically. Panting, gasping, staggering from the exhaustion of moving across the fungus quicksand, he made his way to the top of the first hill, plunged down into a little valley on the farther side, and up another slope. He left a clear trail behind him of disturbed and scurrying creatures that had inevitably found a home in the mass of living stuff. Small sinuous centipedes scuttled here and there, roused by his passage. At the bottom of his footprints writhed fat white worms. Beetles popped into view and vanished again.... A half mile across the range and Burl could go no farther. He stumbled and fell and lay there, gasping hoarsely. Overhead the gray sky had become a deep-red which was rapidly melting into that redness too deep to be seen except as black. But there was still some light from the west. Burl sobbed for breath in a little hollow, his sharp-toothed club still clasped in his hands. Something huge, with wings like sails, soared in silhouette against the sunset. Burl lay motionless, breathing in great gasps, his limbs refusing to lift him. The sound of the army ants continued. At last, above the crest of the last hillock he had surmounted, two tiny glistening antennae appeared, then the small, deadly shape of an army ant. The forerunner of its horde, it moved deliberately forward, waving its antennae ceaselessly. It made its way toward Burl, tiny clickings coming from its limbs. A little wisp of vapor swirled toward the ant. It was the vapor that had gathered over the whole range of hills as a thin, low cloud. It enveloped the ant which seemed to be thrown into a strange convulsion, throwing itself about, legs moving aimlessly. If it had been an animal instead of an insect, it would have choked and gasped. But ants breathe through air-holes in their abdomens. It writhed helplessly on the spongy stuff across which it had been moving. Burl was conscious of a strange sensation. His body felt remarkably warm. It felt hot. It was an unparalleled sensation, because Burl had no experience of fire or the heat of the sun. The only warmth he had ever known was when huddling together with his tribesmen in some hiding-place to avoid the damp chill of the night. Then, the heat of their breath and flesh helped to combat discomfort. But this was a fiercer heat. It was intolerable. Burl moved his body with a tremendous effort and for a moment the fungus soil was cool beneath him. Then the sensation of hotness began again and increased until Burl's skin was reddened and inflamed.