They did, suddenly—a shrill tittering like a blasphemy of childish laughter. Their eyes shone. They rushed in, running wetly along the ledge, reaching up out of the water to claw at ankles, laughing. Inside his tough flat belly Harker's guts turned over. McLaren yelled and kicked. Claws raked his ankle, spiny needle-sharp things like thorns. Sim ran his spear clean through a golden breast. There were no bones in it. The body was light and membranous, and the blood that ran out was sticky and greenish, like sap. Harker kicked two of the things back in the river, swung his spear like a ball bat and knocked two more off the ledge—they were unbelievably light—and shouted, "Up there, that high ledge. I don't think they can climb that." He thrust McLaren bodily past him and helped Sim fight a rearguard action while they all climbed a rotten and difficult transit. McLaren crouched at the top and hurled chunks of stone at the attackers. There was a great crack running up and clear across the cavern roof, scar of some ancient earthquake. Presently a small slide started. "Okay," Harker panted. "Quit before you bring the roof down. They can't follow us." The plannies were equipped for swimming, not climbing. They clawed angrily and slipped back, and then retreated sullenly to the water. Abruptly they seized the body with Sim's spear through it and devoured it, quarreling fiercely over it. McLaren leaned over the edge and was sick. Harker didn't feel so good himself. He got up and went on. Sim helped McLaren, whose ankle was bleeding badly. This higher ledge angled up and around the wall of the great lake-cavern. It was cooler and drier here, and the lichens thinned out, and vanished, leaving total darkness. Harker yelled once. From the echo of his voice the place was enormous. Down below in the black water golden bodies streaked like comets in an ebon universe, going somewhere, going fast. Harker felt his way carefully along. His skin twitched with a nervous impulse of danger, a sense of something unseen, unnatural, and wicked. Sim said, "I hear something." They stopped. The blind air lay heavy with a subtle fragrance, spicy and pleasant, yet somehow unclean. The water sighed lazily far below. Somewhere ahead was a smooth rushing noise which Harker guessed was the river inlet. But none of that was what Sim meant. He meant