ILLUSTRATIVE NOTES. 331 



in temperate or cold countries, we put the fact that the swallow is 

 not satisfied with less than one thousand flies per diem; that a couple 

 of sparrows carry home to their young four thousand three hundred 

 caterpillars or beetles weekly; a tomtit three hundred daily; we see 

 at once the evil and the remedy. We quote these figures from M. 

 Quatrefages (Souvenirs), and from a letter written by Mr. Walter 

 Trevelyan to the editor of " The Birds of Great Britain," translated 

 in the Revue Britannique, July 7, 1850. 



I offer the reader a very incomplete summary of the services ren- 

 dered to us by the birds of our climate. 



Many are the assiduous guardians of our herds. The heron garde- 

 boeuf, making use of his bill as a lancet, cuts the flesh of the ox to 

 extract from it a parasitical worm which sucks the blood and life of 

 the animal. The wagtails and the starlings render very similar 

 services to our cattle. The swallows destroy myriads of winged 

 insects which never rest, and which we see dancing in the sun's rays ; 

 gnats, midges, flies. The goat-suckers and the martinets, twilight 

 hunters, effect the disappearance of the cockchafers, the gnats, the 

 moths, and a swarm of nibbling insects (rongeurs), which work only 

 by night. The magpie hunts after the insects which, concealed be- 

 neath the bark of the tree, live upon its sap. The humming-bird, 

 the fly-catcher, the soui-mangas, in tropical countries, purify the 

 chalice of the flower. The bee-eater, in all lands, carries on a fierce 

 hostility against the wasps which ruin our fruit. The goldfinch, 

 partial to uncultivated soil and the seeds of the thistle, prevents the 

 latter from spreading over the ground. Our garden birds, the chaf- 

 finches, blackcaps, blackbirds, tits, strip our fruit-bushes and great trees 

 of the grubs, caterpillars, and beetles, whose ravages would be incal- 

 culable. A large number of these insects remain during winter in 

 the egg or the larva, waiting for spring to burst into life ; but in 

 this state they are diligently hunted up by the mavis, the wren, the 

 troglodyte. The former turn over the leaves which strew the earth ; 

 the latter climb to the loftiest branches, or clear out the trunk. In 

 wet meadows, you may see the crows and storks boring the ground 



