A huge gawky vehicle seemed to be waiting for the ship to land; it shot out from the huddle of gray buildings almost the moment they touched down. Jack slipped into the furs that he had pulled from stores, and went out through the entrance lock and down the ladder to meet the dark furry creatures that were bundling out of the vehicle below. The electronic language translator was strapped to his chest. Five minutes later he reappeared, frost forming on his blue collar, his face white as he looked at Dal. "You'd better get down there right away," he said, "and take your micro-surgical instruments. Tiger, give me a hand with the anaesthesia tanks. They're keeping a patient alive with a heart-lung machine right now, and they can't finish the job. It looks like it might be bad." * * * * * The Moruan who escorted them across the city to the hospital was a huge shaggy creature who left no question of the evolutionary line of his people. Except for the flattened nose, the high forehead and the fur-less hand with opposing thumb, he looked for all the world like a mammoth edition of the Kodiak bears Dal had seen displayed at the natural history museum in Hospital Philadelphia. Like all creatures with oxygen-and-water based metabolisms, the Moruans could trace their evolutionary line to minute one-celled salt-water creatures; but with the bitter cold of the planet, the first land-creatures to emerge from the primeval swamp of Morua VIII had developed the heavy furs and the hibernation characteristics of bear-like mammals. They towered over Dal, and even Tiger seemed dwarfed by their immense chest girth and powerful shoulders. As the surface car hurried toward the hospital, Dal probed for more information. The Moruan's voice was a hoarse growl which nearly deafened the Earthmen in the confined quarters of the car but Dal with the aid of the translator could piece together what had happened. More sophisticated in medical knowledge than most races in the galaxy, the Moruans had learned a great deal from their contact with Hospital Earth physicians. They actually did have a remarkable grasp of physiology and biochemistry, and constantly sought to learn more. They had already found ways to grow replacement organs from embryonic grafts, the Moruan said, and by copying the techniques used by the surgeons of Hospital Earth, their own surgeons had attempted the delicate job of replacing a diseased organ with a new, healthy one in a young male afflicted with cancer. Dal looked up at the Moruan doctor. "What organ were you replacing?" he asked suspiciously. "Oh, not the entire organ, just a segment," the Moruan said. "The tumor had caused an obstructive pneumonia--" "Are you talking about a segment of _lung_?" Dal said, almost choking. "Of course. That's where the tumor was." Dal swallowed hard. "So you just decided to replace a segment." "Yes. But something has gone wrong, we don't know what."