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Passing to other sea fowl and shore birds, we soon meet with 

 species that form a very slender nest upon the ground. This 

 may vary all the way from a shallow excavation the bird scoops 

 out to contain its eggs, to where they, in other species, use an 

 extremely meager supply of some material, as grass or moss, to 

 form a very slender nest in the aforesaid hollow. These are rudi- 

 mentary ground nests of the simplest character; and many gulls, 

 snipe, plover, and their kin, never construct any other kind. On 

 the other hand the puffins dig a shallow burrow for themselves, 

 or they may occupy the burrow of some animal — as that of a 

 rabbit — in which to lay their single egg for hatching (Frater- 

 cula); while many cormorants build quite a massive nest of sea- 

 weed upon the rocks near the sea, and lay several eggs. 



Flamingoes — birds related to certain waders upon one hand 

 and to the swans, geese, and their allies upon the other — con- 

 struct upon the ground a most remarkable nest, totally unlike 

 anything found in either group. It is several feet high and com- 

 posed of mud, with a shallow excavation at the smaller end on 

 top, in which the eggs of this species are laid. 



Still more singular are the habits of the megapodes of some 

 parts of the Australian region. These birds, as a rule, are about 

 as large as a ptarmigan, and they bury their eggs in the ground, 

 or else cover them over with a mound of earth, sticks, leaves, 

 and similar material. In these situations the young are hatched 

 out without any assistance from the old birds, and the former are 

 highly developed at birth, being full-feathered and fully capable 

 of caring for themselves. 



Most ducks, geese, and swans build their nests upon the ground 

 near the water's edge, but in Africa they have at least one species 

 of goose that builds high up in trees, while our own common 

 woodduck builds in the hollow trunk of some dead tree, or usu- 

 ally in a hollow, horizontal limb many feet above the ground. 



As we pass to some of the higher groups of birds, we meet with 

 quite a number that build or lay their eggs in the hollows of 

 trees. These hollows may simply be the natural ones, or the nat- 

 ural ones cleaned out by the birds; or they may be excavations 

 made wholly by the birds themselves, as among the woodpeck- 

 ers. Among some of the great hornbills of the east we find cer- 

 tain species that breed in holes of trees, and the male bird, after 

 the hen begins to sit. plasters up the entrance with mud, leaving 

 only a small hole, through which he feeds her during the time 

 incubation lasts. 



