"It was," said Joyce grimly. "Look at the pool. That'll tell you where it went."

The black, secretive surface was bubbling and waving as though, down in its depths, a terrific fight were taking place.

"Something came up and dragged our ten-legged lizard down to its den.

Then that something's brothers got onto the fact that a feast was being held, and rushed in. That pool would be no place for a before-breakfast dip!"

Wichter started to say something in reply, then gazed, hypnotized, at the opposite wall of the jungle.

From the dense screen of lavender foliage stretched a glistening, scale-armored neck, as thick as a man's body at its thinnest point, which was just behind a tremendous-jawed crocodilian head. It tapered back for a distance of at least thirty feet, to merge into a body as big as that of a terrestial whale, that was supported by four squat, ponderous legs.

Moving with surprising rapidity, the enormous thing slid into the mud and began ploughing a way, belly deep, toward the pool. Shapeless, slow-writhing forms were cast up in its wake, to quiver for a moment in the sunlight and then melt below the mud again.

One of the bloated, formless mud-crawlers was snapped up in the huge jaws with an abrupt plunge of the long neck, and the monster began to feed, hog-like, s...o...b..ring over the loathsome carca.s.s.

Wichter shook his head, half in fanatical eagerness, half in despair.

"I'd like to stay and see more," he said with a sigh, "but if that's the kind of creatures we're apt to encounter in the Zeudian jungle, we'd better be going at once--"

"Sh-h!" snapped Joyce. Then, in a barely audible whisper: "I think the thing heard your voice!"

The monster had abruptly ceased its feeding. Its head, thrust high in the air, was waving inquisitively from side to side. Suddenly it expelled the air from its vast lungs in a roaring cough--and started directly for their tree.

"Shoot!" cried Wichter, raising his gun.

Moving with the speed of an express train, the monster had almost got to their overhanging branch before they could pull the triggers. Both sh.e.l.ls imbedded themselves in the enormous chest, just as the long neck reached up for them. And at once things began to happen with cataclysmic rapidity.

Almost with their impact the sh.e.l.ls exploded. The monster stopped, with a great hole torn in its body. Then, dying on its feet, it thrust its great head up and its huge jaws crunched over the branch to which its two puny destroyers were clinging.

With all its dozens of tons of weight, it jerked in a gargantuan death agony. The tree, enormous as it was, shook with it, and the branch itself was tossed as though in a hurricane.

There was a splintering sound. Wichter and Joyce dropped their guns to cling more tightly to the bole of the drooping branch that was their only security. The guns glanced off the mountainous body--and, with a last convulsion of the mighty legs, were swept underneath!

The monster was still at last, its insensate jaws yet gripping the bough. The two men looked at each other in speechless consternation.

The sh.e.l.l a mile off through the dreadful jungle.... Themselves, helpless without their guns....

"Well," said Joyce at last. "I guess we'd better be on our way.

Waiting here, thinking it over, won't help any. Lucky there's no night, for a couple of weeks at least, to come stealing down on us."

He started down the great trunk, with Wichter following close behind.

Walking as rapidly as they could, they hurried back along the tunneled trail toward their sh.e.l.l.

They hadn't covered a hundred yards when they heard a mighty crashing of underbrush behind them. Glancing back, they saw tooth-studded jaws gaping cavernously at the end of a thirty-foot neck--little, dead-looking eyes glaring at them--a hundred-foot body smashing its way over the trap-bushes and through tangles of vines and down-drooping branches.

"The mate to the thing we killed back there!" Joyce panted. "Run, for G.o.d's sake!"

Wichter needed no urging. He hadn't an ounce of fear in his spare, small body. But he had an overwhelming desire to get back to Earth and deliver his message. He was trembling as he raced after Joyce, thirty feet to a bound, ducking his head to avoid hitting the thick lavender foliage that roofed the trail.

"One of us must get through!" he panted over and over. "One of us must make it!"

It was speedily apparent that they could never outrun their pursuer.

The reaching jaws were only a few yards behind them now.

"You go," called Joyce, sobbing for breath. He slowed his pace deliberately.

"No--you--" Wichter slowed too. In a frenzy, Joyce shoved him along the trail.

"I tell you--"

He got no further. In front of them, where there had appeared to be solid ground, they suddenly saw a yawning pit. Desperately, they tried to veer aside, but they were too close. Their last long birdlike leap carried them over the edge. They fell, far down, into a deep chasm, splashing into a shallow pool of water.

A few clods of earth cascaded after them as the monster above dug its great splay feet into the ground and checked its rush in time to keep from falling after them. Then the top of the pit slowly darkened as a covering of some sort slid across it. They were in a prison as profoundly quiet and utterly black as a tomb.

"Dorn," shouted Joyce. "Are you all right?"

"Yes," came a voice in the near darkness. "And you?"

"I'm still in one piece as far as I can feel." There was a splashing noise. He waded toward it and in a moment his outstretched hand touched the professor's shoulder.

"This is a fine mess," he observed shakily. "We got away from those tooth-lined jaws, all right, but I'm wondering if we're much better off than we would have been if we hadn't escaped."

"I'm wondering the same thing." Wichter's voice was strained. "Did you see the way the top of the pit closed above us? That means we're in a trap. And a most ingenious trap it is, too! The roof of it is camouflaged until it looks exactly like the rest of the trail floor.

The water in here is just shallow enough to let large animals break their necks when they fall in and just deep enough to preserve small animals--like ourselves--alive. We're in the hands of some sort of reasoning, intelligent beings, Joyce!"

"In that case," said Joyce with a shudder, "we'd better do our best to get out of here!"

But this was found to be impossible. They couldn't climb up out of the pit, and nowhere could they feel any openings in the walls. Only smooth, impenetrable stone met their questing fingers.

"It looks as though we're in to stay," said Joyce finally. "At least until our Zeudian hosts, whatever kind of creatures they may be, come and take us out. What'll we do then? Sail in and die fighting? Or go peaceably along with them--a.s.suming we aren't killed at once--on the chance that we can make a break later?"

"I'd advise the latter," answered Wichter. "There is a small animal on our own planet whose example might be a good one for us to follow.

That's the 'possum." He stopped abruptly, and gripped Joyce's arm.

From the opposite side of the pit came a grating sound. A crack of greenish light appeared, low down near the water. This widened jerkily as though a door were being hoisted by some sort of pulley arrangement. The walls of the pit began to glow faintly with reflected light.

"Down," breathed Wichter.

Noiselessly they let themselves sink into the water until they were floating, eyes closed and motionless, on the surface. Playing dead to the best of their ability, they waited for what might happen next.

They heard a splashing near the open rock door. The splashing neared them, and high-pitched hissing syllables came to their ears--variegated sounds that resembled excited conversation in some unknown language.