COLOURS AND PATTERNS OF BIRDS loi 



are both brilliantly coloured, usually alike, although there is the 

 odd case of the Eclectus parrots, that I have already mentioned, 

 where one sex is green, the other scarlet. 



When birds are hatched, some, like ducklings and chickens, are bom 

 with a warm coating of down feathers, and are able to run about, 

 see and peck almost as soon as their coats are dry. Others, such 

 as the chicks of most of the famUiar singing birds, come into 

 the world helpless, blind and naked, entirely dependent on the 

 care of their parents. We have seen that among mammals the con- 

 dition of the young at birth depends on the habits rather than on the 

 families to which the animals belong. The older naturalists, misled 

 by seeing the condition of the young nestlings alike in many large 

 groups, thought that it depended more on relationship than on habits, 

 but there are so many differences, among nearly allied birds, that it 

 seems to be a simple adaptation to the conditions. If the eggs are laid 

 in safe, inaccessible places, as in nests on trees, or in holes, the young 

 are usually helpless. If they are laid where the young chicks may 

 have to take refuge in the water, or to hide in the herbage at any 

 moment, they are hatched only when the chicks are able to swim or to 

 run about. When the young are born in a precocious condition, the 

 eggs are larger in proportion to the size of the parents and take longer 

 to incubate. The average time of incubation is from eighteen to 

 twenty-six days ; humming-birds, which lay small eggs even in 

 proportion to their small size, brood over them for less than a fort- 

 night, and the newly hatched young are naked and helpless. 

 Ostriches and their allies lay eggs which are very large even in 

 proportion to the large size of the parents, and when the chicks come 

 out they are able to run about almost at once. At the ostrich 

 farm of Mr. Carl Hagenbeck, in Hamburg, I have seen the actual 

 hatching of young ostriches from eggs that had been brooded in an 

 incubator. At the right time, when the chick had begun to break 

 its way through the hard shell, the operator helped the process, the 

 little bird came out, and in a few minutes was able to stand up and 

 take its first meal of pounded shell, whilst in less than an hour it was 

 running about on the warm sand of the floor of the nursery prepared 

 for it, and taking its food without any assistance. So also young 

 emus, rheas and cassowaries, tinamous, all the game birds, rails, 

 cranes and bustards are clothed and active when they are hatched, 

 and are able to follow their parents on the ground almost at once. 

 The sand-grouse, which have the habits of game birds, although 

 related to the pigeons, are born in an active condition. Shore and 



