But then, to be sure, they had never looked for them before.

They were all the time running into trails of mink, or weasel, or wildcat; and it seemed to them as if the world had suddenly become quite full of foxes.

They were painfully surprised, for they had never thought there were so many disagreeable creatures in the world.

You see, being so young and inexperienced, it never occurred to them that one fox or one weasel could make quite a lot of trails.

So they kept having palpitations every other minute.
"It was just as well, however, that they got such an exaggerated idea of the numbers of their enemies.