feathers; in that of the domestic fowl, who raises his head and neck, crows, and has a pretty trick of scraping the ground with his wing. Many other birds perform special antics suited to the display of their special plumage. Among the most varied and remarkable are those of the Birds of Paradise, which drop through the air, hang upside down on tree twigs, and pose themselves variously (often warbling the while seductive notes) according to the particular beauties which distinguish each species. Cranes and some other birds dance in groups at the mating season--really dance, making steps and jumps with the legs and movements of the wings--in rhythm. Reptiles do only a little in the way of display. The male newt gets a crest in the spring like the wanton lapwing of Tennyson, and a splendid orange-red colour on the belly. Male fishes often develop "display" colours at the breeding season, and it is a mistake to suppose that their eyes and brains are not sensitive to colour. We have a familiar instance in the male of our common little stickleback, who, in early summer, builds, in his native pond, his nest of fragments of weed cemented together, with a wide entrance and a back door. He then becomes brilliant blood-red on the belly (he was white before) and dark green on the back, and swims about near the nest, and has an occasional fight with a competitive neighbour, whilst hustling and shepherding any female stickleback he may meet so as to make her enter it. She enters it alone, and lays an egg, or, perhaps, two or three, and then goes out by the back-door! The male, well pleased, at once goes into the nest, fertilizes the eggs, and swims out again to get another contribution to his future family. After several females have thus deposited eggs in his nest, and he has fertilized them, he keeps guard for many days whilst the young are developing. Even when they are hatched he is in constant attendance on them, for there is danger of their being eaten--not by other males, who are as busy as he is, but by the emancipated females, who neither build the nest nor care for the young, but just lay an egg here and an egg there when invited, and pursue a selfish life of amusement and voracious feeding.