"Do you really think this is necessary?" the assistant inspector asked. He had already requested a transfer to Flight Control.
"Sure it is," the senior inspector said. "Can't tell what these ships might bring in."
"I suppose so," the assistant said. "Still, a Martian whoosis wouldn't even be able to live on Earth. Would it?"
"How should I know?" the senior inspector said. "I'm no botanist. Maybe they don't know, either."
"Seems like a waste of—hey!"
"What is it?" the senior inspector asked.
"I thought I saw something," the assistant said. "Looked a little like a palmetto bug. Over by that shelf."
The senior inspector adjusted his respirator more snugly over his face and motioned to his assistant to do the same. He advanced slowly toward the shelf, unfastening a second nozzle from the pressure tank on his back. He turned it on, and a cloud of greenish gas sprayed out.
"There," the senior inspector said. "That should take care of your bug." He knelt down and looked under the shelf. "Nothing here."
"It was probably a shadow," the assistant said.