nation after nation, but at a terrible cost. Lungs increased in size to secure the oxygen on which life depended, but the poison, inhaled at every breath, left the few survivors sickly and filled with a perpetual weariness. Their minds lacked the energy to cope with new problems or transmit the knowledge which in one degree or another, they possessed.

And after thirty thousand years, Burl, a direct descendant of the first president of the Universal Republic, crept through a forest of toadstools and fungus growths. He was ignorant of fire, or metals, of the uses of stone and wood. A single garment covered him. His language was a scanty group of a few hundred labial sounds, conveying no abstractions and few concrete things.

He was ignorant of the uses of wood. There was no wood in the scanty territory furtively inhabited by his tribe. With the increase in heat and humidity the trees had begun to die out. Those of northern climes went first, the oaks, the cedars, the maples. Then the pines—the beeches went early—the cypresses, and finally even the forests of the jungles vanished. Only grasses and reeds, bamboos and their kin, were able to flourish in the new, steaming atmosphere. The thick jungles gave place to dense thickets of grasses and ferns, now become treeferns again.

And then the fungi took their place. Flourishing as never before, flourishing on a planet of torrid heat and perpetual miasma, on whose surface the sun never shone directly because of an ever-thickening bank of clouds that hung sullenly overhead, the fungi sprang up. About the dank pools that festered over the surface of the earth, fungus growths began to cluster. Of every imaginable shade and color, of all monstrous forms and malignant purposes, of huge size and flabby volume, they spread over the land.

The grasses and ferns gave place to them. Squat footstools, flaking molds, evil-smelling yeasts, vast mounds of fungi inextricably mingled as to species, but growing, forever growing and exhaling an odor of dark places.

The strange growths now grouped themselves in forests, horrible travesties on the vegetation they had succeeded. They grew and grew with feverish intensity beneath a clouded or a haze-obscured sky, while above them fluttered gigantic butterflies and huge moths, sipping daintily of their corruption.

The insects alone of all the animal world above water, were able to endure the change. They multiplied exceedingly, and enlarged themselves in the thickened air. The solitary vegetation—as distinct from fungus growths—that had survived, was now a degenerate form of the cabbages that had once fed peasants. On those rank, colossal masses of foliage, the stolid grubs and caterpillars ate themselves to maturity, then swung below in strong cocoons to sleep the sleep of metamorphosis from which they emerged to spread their wings and fly.

The tiniest butterflies of former days had increased their span until their gaily colored wings should be described in terms of feet, while the larger emperor moths extended their purple sails to a breadth of yards upon yards. Burl himself would have been dwarfed beneath the overshadowing fabric of their wings.

It was fortunate that they, the largest flying creatures, were harmless or nearly so. Burl's fellow tribesmen sometimes came upon a cocoon just about to open, and waited patiently beside it until the beautiful creature within broke through its matted shell and came out into the sunlight.

Then, before it had gathered energy from the air, and before its wings had swelled to strength and firmness, the tribesmen fell upon it, tearing the filmy, delicate wings from its body and the limbs from its carcass. Then, when it lay helpless before them, they carried away the juicy, meat-filled limbs to be eaten, leaving the still living body to stare helplessly at this strange world through its many faceted eyes, and become a prey to the voracious ants who would soon clamber upon it and carry it away in tiny fragments to their underground city.

Not all the insect world was so helpless or so unthreatening. Burl knew of wasps almost the length of his own body who possessed stings that were instantly fatal. To every species of wasp, however, some other insect is predestined prey, and the furtive members of Burl's tribe feared them but little as they sought only the prey to which their instinct led them.

Bees were similarly aloof. They were hard put to it for existence, those bees. Few flowers bloomed, and they were reduced to expedients once considered signs of degeneracy in their race. Bubbling yeasts and fouler things, occasionally the nectarless blooms of the rank, giant cabbages. Burl knew the bees. They droned overhead, nearly as large as he was himself, their bulging eyes gazing at him with abstracted preoccupation. And crickets, and beetles, and spiders—

Burl knew spiders! His grandfather had been the prey of one of the hunting tarantulas, which had leaped with incredible ferocity from his excavated tunnel in the earth. A vertical pit in the ground, two feet in diameter, went down for twenty feet. At the bottom of that lair the black-bellied monster waited for the tiny sounds that would warn him of prey approaching his hiding-place (Lycosa fasciata).

Burl's grandfather had been careless, and the terrible shrieks he uttered as the horrible monster darted from the pit and seized him had lingered vaguely in Burl's mind ever since. Burl had seen, too, the monster webs of another species of spider, and watched from a safe distance as the misshapen body of the huge creature sucked the juices from a three-foot cricket that had become entangled in its trap.

Burl had remembered the strange stripes of yellow and black and silver that crossed upon its abdomen (Epiera fasciata). He had been fascinated by the struggles of the imprisoned insect, coiled in a hopeless tangle of sticky, gummy ropes the thickness of Burl's finger, cast about its body before the spider made any attempt to approach.

Burl knew these dangers. They were a part of his life. It was his accustomedness to them, and that of his ancestors, that made his existence possible. He was able to evade them; so he survived. A moment of carelessness, an instant's relaxation of his habitual caution, and he would be one with his forebears, forgotten meals of long-dead, inhuman monsters.

Three days before, Burl had crouched behind a bulky, shapeless fungus growth while he watched a furious duel between two huge horned beetles. Their jaws, gaping wide, clicked and clashed upon each other's impenetrable armor. Their legs crashed like so many cymbals as their polished surfaces ground and struck against each other. They were fighting over some particularly attractive bit of carrion.

Burl had watched with all his eyes until a gaping orifice appeared in the armor of the smaller of the two. It uttered a shrill cry, or seemed to cry out. The noise was, actually, the tearing of the horny stuff beneath the victorious jaws of the adversary.

The wounded beetle struggled more and more feebly. At last it collapsed, and the conqueror placidly began to eat the conquered before life was extinct.

Burl waited until the meal was finished, and then approached the scene with caution. An ant—the forerunner of many—was already inspecting the carcass.

Burl usually ignored the ants. They were stupid, short-sighted insects, and not hunters. Save when attacked, they offered no injury. They were scavengers, on the lookout for the dead and dying, but they would fight viciously if their prey were questioned, and they were dangerous opponents. They were from three inches, for the tiny black ants, to a foot for the large termites.

Burl was hasty when he heard the tiny clickings of their limbs as they approached. He seized the sharp-pointed snout of the victim, detached from the body, and fled from the scene.

Later, he inspected his find with curiosity. The smaller victim had been a minotaur beetle, with a sharp-pointed horn like