It glared down at Harley. The abyss of a mouth opened as though again giving vent to silent, infernal laughter. Then, with the noise of a landslide, the giant form settled slowly to the ground. The rock half-moons of curtains dropped over the expressionless, dull eyes. The whole great figure quivered, and grew still. It lay without movement, stretched along the ground like a craggy, opalescent hill. * * * * * Dazed, stunned by such fantastic behavior, Harley struggled wearily to his feet. He had been a dead man as surely as though shot with a ray-gun. One twitch of those terrible rock pincers would have broken him in two pieces. It had seemed as though that deadly twitch were surely forthcoming. And then the thing had released him--and had lain down to go to sleep! Or was it asleep? He took a few slow steps away from it, expecting to see the three great tentacles flash out to capture him as a cat claws at a mouse that thinks it is escaping. The arms didn't move. Astounding as it was, Harley was free to run away if he chose. Why was that? A hint of a clue to the creature's action began to unfold in his mind. When he had first laid eyes on it, in daylight, it was asleep. It had not pursued him during the preceding day, which argued that again it was asleep. And now, with the first touch of dawn, it was once more quiet, immobile. The answer seemed to be that it was entirely nocturnal; that for some obscure, unguessable reason sunlight induced in it a state of suspended animation. It seemed an insane theory, but no other surmise was remotely reasonable. But if it were invariably sunk in a coma during daylight, why had it delayed killing him just a moment ago? Its every act indicated that it possessed intelligence of a high order. It was more than probable that it realized its limitation--why hadn't it acted in accordance with that realization? On thinking it over, he believed he had the answer to that, too. He remembered the way the gaping mouth had seemed to express devilish mirth. The thing was playing with him. That was all. It had saved him for another night of hopeless flight and infallible trailing through the forests of Z-40. He gazed at the monster in a frenzy of impotent rage and fear. If only he could kill it somehow in its sleep! But he couldn't. In no way could he harm it. Secure in its silicate covering, it was impervious to his wildest attempts at destruction. And it knew it, too; hadn't it laughed just before sinking down to slumber through the asteroidal day? With his Sco drill he might have pierced that silicon dioxide armor till he reached the creature's gritty flesh. Then he could have used his ray-pistol, possibly disintegrating all its vitals and leaving only an empty rock shell sprawling hugely there in the trampled underbrush.