Sometimes when you are walking in the garden in England and looking at the geraniums in your flowerbeds, you will see a little brown moth hovering over one of them, and putting a long, slender thread-like thing that we call a proboscis (though we call an elephant's trunk a proboscis too) right down into the centre of the flower. _His_ wings move so fast that you can hardly see them, and in a second or two _he_ will dart away too, so quickly that you only know he is gone, and then, all of a sudden, you will see him again, hovering over another geranium and probing it with his wonderful, long, thin proboscis. It is a tube, that proboscis, and through it, the moth is sucking up the nectar of the flower, which is what it lives on. That moth is the humming-bird hawk-moth, and, if you have seen it, you have seen what looks more like a Humming-bird than anything else in England. It hovers over or under or in front of a flower, as the Humming-birds do, it keeps moving its wings in the same rapid way as they move theirs, and making the same humming noise with them, and it puts a long, slender, little brown thing, that looks _something_ like the beak of a Humming-bird, right down into the flower, and sucks up the nectar that is in it, which is just what a Humming-bird does. So if the humming-bird moth were bright and gleaming, as Humming-birds--sunbeams--are, it would seem to be a Humming-bird and not a moth at all. But you must not think that it really would be one. Oh no, it never could be, because it is an insect, and an insect is a very different thing to a bird. The humming-bird moth and the Humming-bird look like each other because they live in the same way and do the same things. They both fly, so they both have wings; and they both sip nectar, so they both have a long thing to stick into the flowers and suck it up with: so they look like each other, but they are not a bit the same. A petticoat, you know, looks a little like an upper skirt, for they both have to be worn round the waist, which makes them the same kind of shape, and when the skirt is part of a white dress then they are of the same colour. But think how different they really are! Why, one is a petticoat and the other is an upper skirt. So you must always remember that, though two animals look the same, they may really be very different.