"We will," Huyghens promised. "I may be wrong, but it seems to me that the number of sphexes climbing the mountain is less than yesterday and the day before. We may have just about crossed the path of their migration. They're thinning out. When we're past their trail, we'll have to look out for night-walkers and the like again. But I think they wiped out all animal life on their migration-route." He was not quite right. He was waked in darkness by the sound of slappings and the grunting of bears. Feather-light puffs of breeze beat upon his face. He struck his belt-lamp sharply and the world was hidden by a whitish film which snatched itself away. Something flapped. Then he saw the stars and the emptiness on the edge of which they camped. Then big white things flapped toward him. Sitka Pete whuffed mightily and swatted. Faro Nell grunted and swung. She caught something in her claws. "Watch this!" said Huyghens. More things strangely-shaped and pallid like human skin reeled and flapped crazily toward him. A huge hairy paw reached up into the light-beam and snatched a flying thing out of it. Another great paw. The three great Kodiaks were on their hind legs, swatting at creatures which flittered insanely, unable to resist the fascination of the glaring lamp. Because of their wild gyrations it was impossible to see them in detail, but they were those unpleasant night-creatures which looked like plucked flying monkeys but were actually something quite different. The bears did not snarl or snap. They swatted, with a remarkable air of business-like competence and purpose. Small mounds of broken things built up about their feet. Suddenly there were no more. Huyghens snapped off the light. The bears crunched and fed busily in the darkness. "Those things are carnivores _and_ blood-suckers, Bordman," said Huyghens calmly. "They drain their victims of blood like vampire-bats--they've some trick of not waking them--and when they're dead the whole tribe eats. But bears have thick fur, and they wake when they're touched. And they're omnivorous. They'll eat anything but sphexes, and like it. You might say that those night-creatures came to lunch. They _are_ it, for the bears, who are living off the country as usual." Bordman uttered a sudden exclamation. He made a tiny light, and blood flowed down his hand. Huyghens passed over his pocket kit of antiseptic and bandages. Bordman stanched the bleeding and bound up his hand. Then he realized that Nugget chewed on something. When he turned the light, Nugget swallowed convulsively. It appeared that he had caught and devoured the creature which had drawn blood from Bordman. But he'd lost none to speak of, at that. In the morning they started along the sloping scarp of the plateau once more. After marching silently for a while, Bordman said: "Robots wouldn't have handled those vampire-things, Huyghens."