They stripped their packs and broke out rations silently. The dry leaves and spongy loam made a comfortable seat, and after a day of hiking the relaxation was bliss. Tinnerman leaned back against the base of the nearest trunk, chewing and gazing up into the bole of the tree. It was dark; but he could make out a giant spherical opacity from which multiple stems projected downward, bending and swelling for a hundred feet until they touched the ground as trunks twelve feet in diameter. Don Abel's voice came out of the shadow. "The monster passed right under here. I'm sitting on the edge of a print. What if it comes back?" Slaker laughed, but not loudly. "Mebbe we're in its nest? We'd hear it. A critter like that--just the shaking of the ground would knock us all a foot into the air." There was a sustained rustle. "What are you doing?" Abel asked querulously. "Making a bed," Slaker snapped. "Do you think it's safe?" Abel asked, though his tone indicated that he suspected one place was as unsafe as another. After a moment, the rustle signified that he too was making a bed. Tinnerman smiled in the dark, amused. He really did not know the other men well; the three had organized an AWOL party on the spur of the moment, knowing that the survey ship would be planetbound for several days. The bark of the tree was thick and rubbery, and Tinnerman found it oddly comfortable. He put his ear against it, hearing a faint melodic humming that seemed to emanate from the interior. It was as though he was auditing the actual life-processes of the alien vegetation--although on this world, _he_ was the alien--and this fascinated him. The other two were soon asleep. Sitting there in silence, the absolute blackness of a strange world's umbra pressing against his eyeballs, Tinnerman realized that this outing, dangerous as it was, offered him a satisfaction he had seldom known. Slaker and Abel had accepted him for what he was not: one of the fellows. Those footprints. Obviously animal--yet so large. Would a pressure of a hundred pounds per square inch depress the earth that much? How much would the total creature weigh? Tinnerman found his pack in the dark and rummaged for his miniature slide rule. The tiny numbers fluoresced as he set up his problem: 144 times the square of 4.5 times pi divided by 20. It came to about 460 tons per print. And how many feet did it have, and how much weight did each carry when at rest? * * * * *