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 proudly. "We made them ourselves, just for
this case."

"You mean you've never attempted this procedure before?"