land-prawn.

This one dodged the thrown flint, scuttled off a few feet and turned,
waving its antennae in what looked like derision. Jack reached for his hip
again, then checked the motion. Pistol cartridges cost like crazy; they
weren't to be wasted in fits of childish pique. Then he reflected that no
cartridge fired at a target is really wasted, and that he hadn't done any
shooting recently. Stooping again, he picked up another stone and tossed
it a foot short and to the left of the prawn. As soon as it was out of his
fingers, his hand went for the butt of the long automatic. It was out and
the safety off before the flint landed; as the prawn fled, he fired from
the hip. The quasi-crustacean disintegrated. He nodded pleasantly.

"Ol' man Holloway's still hitting things he shoots at."

Was a time, not so long ago, when he took his abilities for granted. Now
he was getting old enough to have to verify them. He thumbed on the safety
and holstered the pistol, then picked up the glove and put it on again.

Never saw so blasted many land-prawns as this summer. They'd been bad last
year, but nothing like this. Even the oldtimers who'd been on Zarathustra
since the first colonization said so. There'd be some simple explanation,
of course; something that would amaze him at his own obtuseness for not
having seen it at once. Maybe the abnormally dry weather had something to
do with it. Or increase of something they ate, or decrease of natural
enemies.

He'd heard that land-prawns had no natural enemies; he questioned that.
Something killed them. He'd seen crushed prawn shells, some of them close
to his camp. Maybe stamped on by something with hoofs, and then picked