Plants four and five times life size glowed green on the wall.  What Weeks had caught they all saw now—­ragged leaves, stripped stems.

“Chewed!” Dane supplied the answer.

It was only one species of plant which had been so mangled.  Other varieties in the same bank showed no signs of disturbance.  But all of that one type had at least one stripped branch and two were virtual skeletons.

“A pest!” said Rip.

“But Sinbad,” Dane began a protest before the memory of the cat’s peculiar actions of the past weeks stopped him.  Sinbad had slipped up, the hunter who had kept the Queen free of the outré alien life which came aboard from time to time with cargo, had not attacked that which had ravaged the hydro plants.  Or if he had done so, he had not, after his usual custom, presented the bodies of the slain to any crew member.

“It looks as if we have something at last,” Ali observed and someone echoed that with a sigh of heartdeep relief.

Chapter XII

STRANGE BEHAVIOR OF A HOOBAT

“All right, so we think we know a little more,” Ali added a moment later.  “Just what are we going to do?  We can’t stay in space forever—­there’re the small items of fuel and supplies and—­”

Rip had come to a decision.  “We’re not going to remain space borne,” he stated with the confidence of one who now saw an open road before him.

“Luna—­” Weeks was plainly doubtful.

“No.  Not after that warn-off.  Terra!”

For a second or two the other three stared at Rip agape.  The audacity and danger of what he suggested was a little stunning.  Since men had taken regularly to space no ship had made a direct landing on their home planet—­all had passed through the quarantine on Luna.  It was not only risky—­it was so unheard of that for some minutes they did not understand him.

“We try to set down at Terraport,” Dane found his tongue first, “and they flame us out—­”

Rip was smiling.  “The trouble with you,” he addressed them all, “is that you think of earth only in terms of Terraport—­”

“Well, there is the Patrol field at Stella,” Weeks agreed doubtfully.  “But we’d be right in the middle of trouble there—­”

“Did we have a regular port on Sargol—­on Limbo—­on fifty others I can name out of our log?” Rip wanted to know.

Ali voiced a new objection.  “So—­we have the luck of Jones and we set down somewhere out of sight.  Then what do we do?”

“We seal ship until we find the pest—­then we bring in a Medic and get to the bottom of the whole thing,” Rip’s confidence was contagious.  Dane almost believed that it could be done that way.

“Did you ever think,” Ali cut in, “what would happen if we were wrong—­if the Queen really is a plague carrier?”

“I said—­we seal the ship—­tight,” countered Shannon.  “And when we earth it’ll be where we won’t have visitors to infect—­”