It could have been, of course. Caterpillars breathe like all insects at every stage of their development. But furry caterpillars breathe through openings which are covered over with matted fur. Here, that matted fur acted to filter the air. The eggs of the caterpillars had been laid before the puffballs were ready to burst. The time of spore-bearing would be over before the grubs were butterflies or moths. These creatures were safe against all enemies--even men. But men groped and blundered in the darkness simply because they did not think to take the fur garments they wore and hold them to their noses to serve as gas-masks or air-filters. The time for that would come, but not yet.
With the docility of despair, Burl's tribe followed him through all the night. When the sky began to pale in the east, they numbly resigned themselves to death. But still they followed.
And in the very early gray light--when only the very ripest of the red puffballs spouted toward a still-dark sky--Burl looked harassedly about him and could have groaned. He was in a little circular clearing, the deadly red things all about him. There was not yet light enough for colors to appear. There was merely a vast stillness everywhere, and a mocking hint of the hot and peppery scent of death-dust--now turned to mud--all about him.
Burl dropped in bitter discouragement. Soon the misty dust-clouds would begin to move about; the reddish haze would form above all this space....
Then, quite suddenly, he lifted his head and whooped. He had heard the sound of running water.
His followers looked at him with dawning hope. Without a word to them, Burl began to run. They followed hastily and quickened their pace when his voice came back in a shout of triumph. In a moment they had emerged from the tangle of fungus growths to stand upon the banks of a wide river--the same river whose gleam Burl had seen the day before, from the farther side of the red puffball plain.
Once before, Burl had floated down a river upon a mushroom raft. That journey had been involuntary. He had been carried far from his tribe and Saya, his heart filled with desolation. But now he viewed the swiftly-running current with delight.
He cast his eyes up and down the bank. Here and there it rose in a low bluff and thick shelf-fungi stretched out above the water. They were adaptations of the fungi that once had grown on trees and now fed upon the incredibly nourishing earth-banks formed of dead growing things. Burl was busy in an instant, stabbing the relatively hard growths with his spear and striving to wrench them free. The tribesmen stared blankly, but at a snapped order they imitated him.