heads replaced."

An agitated voice came from the visiplate on the captain's desk: "Tuning
in, sir."

Lawton stopped pacing abruptly. He swung about and grasped the desk edge
with both hands, his head touching Forrester's as the two men stared
down at the horizontal face of petty officer James Caldwell.

Caldwell wasn't more than twenty-two or three, but the screen's
opalescence silvered his hair and misted the outlines of his jaw, giving
him an aspect of senility.

"Well, young man," Forrester growled. "What is it? What do you want?"

The irritation in the captain's voice seemed to increase Caldwell's
agitation. Lawton had to say: "All right, lad, let's have it," before
the information which he had seemed bursting to impart could be wrenched
out of him.

It came in erratic spurts. "The bubble is all blooming, sir. All around
inside there are big yellow and purple growths. It started up above,
and--and spread around. First there was just a clouding over of the sky,
sir, and then--stalks shot out."

For a moment Lawton felt as though all sanity had been squeezed from his
brain. Twice he started to ask a question and thought better of it.

Pumpings were superfluous when he could confirm Caldwell's statement in
half a minute for himself. If Caldwell had cracked up--

Caldwell hadn't cracked. When Lawton walked to the quartz port and
stared down all the blood drained from his face.

The vegetation was luxuriant, and unearthly. Floating in the sky were
serpentine tendrils as thick as a man's wrist, purplish flowers and ropy
fungus growths. They twisted and writhed and shot out in all directions,
creating a tangle immediately beneath him and curving up toward the ship
amidst a welter of seed pods.

He could see the seeds dropping--dropping from pods which reminded him
of the darkly horned skate egg sheaths which he had collected in his
boyhood from sea beaches at ebb tide.

It was the _unwholesomeness_ of the vegetation which chiefly unnerved
him. It looked dank, malarial. There were decaying patches on the fungus
growths and a miasmal mist was descending from it toward the ship.

The control room was completely still when he turned from the quartz
port to meet Forrester's startled gaze.

"Dave, what does it mean?" The question burst explosively from the
captain's lips.

"It means--life has appeared and evolved and grown rotten ripe inside
the bubble, sir. All in the space of an hour or so."

"But that's-