Of course you know that a lobster is not red until it is boiled, but is nearly black all over. And of course you know, too, that one of its great claws is always a good deal larger and stouter than the other. Sometimes people think that the reason of this is that at some previous time the animal had lost one of his claws through some accident, and was growing a new one, and that the new limb had not yet had time to reach its full size. However, this is not the case, for one claw of a lobster is always a good deal bigger than the other; and the real reason is that the two claws are used for different purposes. The larger claw is a weapon, with which the animal fights, while the smaller one is an anchor, with which he clings to the weeds which grow on the rocks at the bottom of the sea. And very often one is quite twice as big as the other. Now I wonder whether you know how a lobster uses his tail. He employs it in swimming, and if you look at it you will find that it is made of several broad, flat plates, which can be spread out very much like the joints of a fan. You will notice, too, that these joints have a fringe of hairs growing all round them. Now when a lobster swims he just stretches his body straight out, and then doubles it suddenly up. As he does so the plates of the tail spread out, and form a kind of very broad and powerful oar, which strikes the water with such force as to drive the animal swiftly backwards. With a single stroke of its tail, indeed, a lobster can dart to a distance of forty or fifty feet, and that so quickly that even the swiftest fishes could scarcely overtake him. Sometimes, however, a lobster swims forwards; and he does this by means, not of his tail, but of five pairs of odd little organs underneath the tail, which we call “swimmerets.” They spring from either side of the soft hinges by which the joints of the tail are fastened together, and each consists of two thin oval plates fringed with long hairs. So each swimmeret really consists of two tiny paddles, and by waving them to and fro in the water the lobster manages to travel along with some little speed. [Illustration: PLATE XXVII THE LOBSTER.] These swimmerets are used for another purpose as well, however, for the mother lobster always glues her eggs to the hairs with which they are fringed, and carries them about with her for some little time. Haven’t you noticed, when you have had shrimps for tea, that a good many of them had clusters of eggs underneath their bodies? Well, if you had put one of those shrimps under a microscope, and examined it very carefully, you would have found that every one of the eggs was firmly glued down to one of the hairs on its swimmerets, where it would have remained until it was hatched. And lobsters carry their eggs about with them in just the same way. PLATE XXVIII THE PRAWN (1)