CHAPTER XIII
RATS
“Let us return for a moment to the rodents, the habitual prey of the night-birds. You do not know them all, by any means, but we ought not to pass them by; for if some, like the hare and the rabbit, are useful to us, still more are very destructive. You remember those two pairs of incisors, so long and sharp, that I told you about when I described the rabbit’s teeth. All rodents have similar incisors. To keep them sharp and prevent them from overlapping too much by growing too long, which would make it impossible for the animal to feed itself, the rodent must wear them down by constant friction as fast as they grow. Consequently, these terrible incisors have, so to speak, no rest; they must always be nibbling something, no matter what. Thus the harm they do us is much greater than you would suspect from the size of the animal. How much actual food does a mouse need for one meal? Very little, unquestionably. A mouse is so small that a single nut will fill its stomach. Don’t think, however, that one day’s ravages are confined to that one nut. After the nut is eaten, the animal will proceed, perhaps, to gnaw a hole in a bag, reduce a piece of cloth to tatters, chew up a [[99]]book, or drill a hole in a board, simply and solely to whet its teeth. And the damage caused by rats and mice in our dwelling-houses is matched by other damage caused by other rodents in the fields. You must make the acquaintance of all these destroyers.”
Norway or Brown Rat
(One-third natural size)
“For my part,” Jules confessed, “I shouldn’t, if I saw it, know the field-mouse that you told us about in your talk on night-birds.”
“I know rats and mice such as we have in the house,” said Emile, “but that’s all.”
“And yet,” rejoined his uncle, “I very much doubt whether you have any real knowledge of the rat. I will begin with it.
“The common or black rat is more than twice the size of a mouse. Its coat is nearly black above, and ashy gray underneath. It lives in granaries, thatched roofs, and abandoned ruins. If it fails to [[100]]find a lodging to its taste, it burrows a hole for itself. It is not a native with us, but is thought to have come from Asia in the wake of the armies returning from the Crusades. To-day the common rat is seldom mentioned in our country; another foreign rodent has come in, the Norway or brown rat, which, being larger than the common rat, has waged war against it and almost wiped out the species. We have not gained by the exchange; quite the contrary, the Norway rat being a much more troublesome creature. The true rat, the black rat, is rare now, especially where the other abounds; and that is why I doubt that any one of you is familiar with it. What you call a rat is more than likely to be one of these Norwegian invaders. Don’t forget the color—black—and you will have no difficulty in recognizing the true rat.