602 THE POPULAR SCIENCE MONTHLY. 



count of the prodigious numbers of field-mice they destroy. Yet the 

 farmers kill these benefactors, and nail their skins upon their shed- 

 doors as trophies and admonitions. This is bad enough, even though 

 it be done in ignorance and not in malice. Toads and creeping things 

 are pursued by numerous wild birds — the snake-eagle, the secretary, 

 the curious South American cuckoos called saurothers, and many other 

 feathered foes. The dumb host of fishes finds eager hunters among 

 the birds, even more than among men. Cormorants and pelicans, 

 gulls and sea-swallows, petrels and albatrosses, have made themselves 

 masters of the sea in a higher sense than the most formidable pirate, 

 for the latter is limited to the water, while the birds, not only by swim- 

 minor and diving snatch the inhabitants of the waters from their own 

 element, but they also capture those fish which, leaving the water for a 

 moment to escape the Scylla of danger from other fishes, throw them- 

 selves into the air and into the power of a hungry and greedy Charybdis. 

 And where is any fish in fresh water safe from the pursuit of birds ? 



No shell or other shelter affords adequate protection to the poor 

 mollusks ; but they, too, have to find their way through the maws of 

 birds into the circulating stream of matter. It is true that they usu- 

 ally serve only as a temporary substitute for something else, and few 

 of the inhabitants of the air live exclusively upon them ; of these are 

 those curious finches, so like the haw -finch, that live in the Galapagos 

 Islands, descendants from South American castaways, which found 

 no corn-grains on the rocks, but a nutritious though unaccustomed 

 substitute in the shell-fish of the beach, whose shells their tough bills 

 could crack with ease. 



The hosts of birds consume immeasurable quantities of insects 

 every day. In no place and no condition are creatures of this class 

 secure from their pursuit. The fat larva, leading a tranquil existence 

 in the depths of decaying wood, is the prey of the sagacious wood- 

 pecker. The portly spider, in her dark corner, does not escape the 

 penetrating eye of the redstart. Little beetles and gnats, carried up 

 into the air by ascending currents, are a welcome game to the high- 

 flying swallows. 



No more than animals can plants escape the demands of the birds' 

 appetite. Of whatever plants can furnish, excepting only the wood, 

 the birds take their tithes. Humming-birds, besides the nectar, de- 

 vour the insects that go in after it. The Australian licmetis digs into 

 orchid-roots and lily-bulbs with a bill admirably adapted to that use. 

 The Polyborus chimango, of Chiloe, digs up freshly planted potatoes, 

 to the ruin of the farmers, and eats them with relish. Some South 

 American birds feed on aromatic leaves, and the New Zealand night- 

 parrot prefers a delicate liverwort to all other food. But so slight is 

 the nourishing power of this plant that the bird has to consume im- 

 mense quantities of it, and his crop is swelled out after each meal 

 enormously. Seeds, berries, and fruits furnish a most welcome sub- 



