As the two humans halted, a flap of loose skin on the belly of the nearest nightmare was pushed aside and a small replica of the monster drew itself out of a sac and wobbled weakly down to the water, curling its neck over to suck up the liquid. After it swallowed the first mouthful, some instinct drew its attention to the watchers. With a shrill hiss it scrambled back to its parent. The head of the larger thing snapped up, swaying back and forth, a snake preparing to strike!
Dard threw himself back, carrying Santee with, him. They were brought up short by the cliff wall, but they dared not turn their backs upon the aroused monster long enough to find hand and foot holds there.
The thing across the pool was on its feet, towering far over them. With a cuff of one paw it sent the infant sprawling to safety before it slewed around kicking up blood-clotted sand. The flat serpent's head went down to a level with the lizardlike shoulders, and from its fanged jaws came a hiss which gathered volume until it rivaled the piercing whistle of a steam-powered engine.
That battle cry aroused its fellow sleepers. But they arose sluggishly, too torpid from their feasting to respond.
Santee shot. The nerve-paralyzing projectile of the stun rifle struck fair between those murderous yellow, unwinding eyes. The skull shattered with a spatter of green ooze. But the thing waded the pool to rush, them, tearing claws outstretched. It should have been dead. But with a broken, empty skull, blinded, it came on!
"No brain in the head!" Dard shouted. "Jump!"
They jumped apart. The advancing horror struck hard against the cliff to cling there stubbornly clawing at the rock. It continued to scream senselessly, bringing the others of its kind into full alertness.
One gave a bound, clearing the pool, to fall upon its wounded companion with tearing jaws and claws. The other three appeared undecided. Their snake heads rose and fell as they hissed. One made to join the battle on the other side of the pool and then retreated.
Daring to hesitate no longer, Dard took careful aim with the ray gun and sent a green beam straight into the distended middle of the creature that rocked from one splayed foot to another on his right. The Terrans had to clear a path past the pool, for to return near the fighters was sure death.
Screaming madly, Dard's quarry clapped both hands over the frightful gaping emptiness the ray had left and wilted forward into the water, sending up a slimy spray of blood and poisonous liquid. With the attention of its two fellows attracted to its struggles Dard darted to join Santee.
Together the humans edged along the cliff wall, their goal the valley beyond the pool. For a few minutes it seemed that they might be able to gain it undetected by the monsters. For one of the unhurt creatures had gone to work on the body in the pool. But when its smaller companion made to join it, fangs and talons threatened, forcing that other to withdraw, hissing fury. As its head swung back and forth it sighted the Terrans. An arching leap brought it after them. Both the length and speed of that bound panicked the cornered men. They scrambled into the meager protection offered by the boulders and fallen rock. Santee's second bullet tore a hole in the sealed breast of the pursuer without slowing its charge. Dard pressed the firing stud on the ray gun. But the responding beam was weak. It clipped the side of thee weaving head, shearing off part of the skull and one eye, and cutting neck muscles so badly that the battered head flopped erratically.
Dard fired again-with no result. The clip left in the weapon must have been exhausted! His ears roared as Santee shot from beside him. But the bullet only nicked the shoulder of the writhing body. Despairing they scuttled and backed away, keeping in among the rough footing. But they were past the pool, in the middle of the valley, on a course which paralleled a path worn deep and smooth by the feet of the monsters.
The scream of the hunter behind them was cut by a trumpeting squeal. A second was bearing down to join in the chase.
"Ahead- three-four-yards"-Dard got out the words between tearing breaths-"hole-too-small-"
He concentrated on reaching that haven, and Santee ran beside him. The hole was a perfectly round one, and from it ran the monorail of the ancient transport system. They threw themselves into the dark, scrambling on until Dard brought up against a heavy object which gave under his weight, slipping on so suddenly that he sprawled face down, the wind driven out of him.
When he caught his breath again he sat up, still groggy. The crack of the rifle filled the tunnel with a blast of sound.
"Got one at last! And it'll block up that hole-for a while anyways. But it ain't healthy in here-they can get in -squeeze themselves altogether and do it. What the-!" The big man ended his report with an exclamation of both outrage and fear.
Dard had breath enough to ask: "What's the matter?"