In color the European lemming is blackish brown above and yellowish white below, while its length is about six inches. Various kinds of rodents known as lemmings are found in North America. The Hudson Bay lemming has a thick, warm fur. Eskimo children use lemming-skins to make clothes for their dolls. RATS The brown rat and the black rat, of course, are only too common everywhere. They seem to have come in the first place from Asia, and have spread to almost all parts of the world. For almost every ship that sails the sea is infested with rats, some of which are nearly certain to make their way ashore at every port at which she touches. Rats are rather formidable animals, for besides being very savage, a number of them will often combine together in order to attack a common foe. We have known a large cat, for example, to be so severely wounded by rats, that after lying in great pain for two or three days it actually died of its injuries. Rats are very bloodthirsty creatures, for if one of their own number is caught in a trap, they will tear it in pieces and devour it. They will enter fowl-houses at night, and kill the birds as they roost upon their perches, while if they can find their way into a rabbit-hutch they will even destroy the rabbits. In barns and farmyards rats are very mischievous, and corn-stacks are often infested by them. How often they get into houses you know too well! But on the other hand, they often do a great deal of good, by devouring substances which would otherwise decay and poison the air; so that they are not altogether without their uses, as people annoyed by them are too apt to suppose. Rats generally have three broods of little ones in the course of the year, and as there are from eight to fourteen in each brood, you can easily understand how it is that these animals multiply so rapidly. MICE Still more plentiful, and almost as mischievous, is the common mouse, which is found both in town and country. And this, too, seems to have been in the first place a native of Asia, and to have since spread to almost all parts of the world. There is no need, of course, to describe its appearance, and most of us are familiar with its habits. So we will pass on at once to one of its near relations which is not quite so well known, namely, the long-tailed field-mouse.