m the surrounding meadows, not singly, or in twos and
threes, as they had before; this time they came together. Squealing
and rustling the grass, they moved toward the fields. It was dark, and
though he could not see them, Marin could hear them. He ordered the
great lights turned on in the area of the fields.

The rats stopped under the glare, milling around uneasily. The dogs
quivered and whined. Marin held them back. The rats resumed their
march, and Marin released the dogs.

The dogs charged in to attack, but didn't dare brave the main mass.
They picked off the stragglers and forced the rats into a tighter
formation. After that the rats were virtually unassailable.

The colonists could have burned the bunched-up rats with the right
equipment, but they didn't have it and couldn't get it for years. Even
if they'd had it, the use of such equipment would endanger the crops,
which they had to save if they could. It was up to the dogs.

The rat formation came to the edge of the fields, and broke. They
could face a common enemy and remain united, but in the presence of
food, they forgot that unity and scattered--hunger was the great
divisor. The dogs leaped joyously in pursuit. They hunted down the
starved rodents, one by one, and killed them as they ate.

When daylight came, the rat menace had ended.

The next week the colonists harvested and processed the food for
storage and immediately planted another crop.

[Illustration]

Marin sat in the lab and tried to analyze the situation. The colony
was moving from crisis to crisis, all of them involving food. In
itself, each critical situation was minor, but lumped together they
could add up to failure. No matter how he looked at it, they just
didn't have the equipment they needed to colonize Glade.

The fault seemed to lie with Biological Survey; they hadn't reported
the presence of pests that were endangering the food supply.
Regardless of what the exec thought about them, Survey knew their
business. If they said there were no mice or rats on Glade, then there
hadn't been any--_when the survey was made_.

The question was: when did they come and how did they get here?

Marin sat and stared at the wall, turning over hypotheses in his mind,
discarding them when they failed to make sense.

His gaze shifted from the wall to the cage of the omnivores, the
squirrel-size forest creature. The most numerous animal on Glade, it
was a commonplace sight to the colonists.