ears 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."

"I see." It was all Dal could do to keep from shouting at the huge
creature. The Moruans had no duplication of organs, such as Earthmen and
certain other races had. A tumor of the lung would mean death ... but
the technique of grafting a culture-grown lung segment to a portion of
natural lung required enormous surgical skill, and the finest
microscopic instruments that could be made in order to suture together
the tiny capillary walls and air tubules. And if one lung were
destroyed, a Moruan had no other to take its place. "Do you have any
micro-surgical instruments at all?"

"Oh, yes," the Moruan rumbled proud