XXIV INTRODUCTION. 



the winter ; and so do four-fiftlis of the Ducks that visit us 

 at the same season. Several others among the waders and 

 water-birds leave certain districts for the purpose of breed- 

 ing, e. g., Otis aurita, Ardea bubulcus, some of the Rails, 

 Terns, Gulls, and others ; and a few birds also wander 

 about, apparently to procure their food with more facility. 



Migrating birds often return regularly to the same 

 spot year after year, and even in many cases to the same 

 nest which they have previously occupied. The wonderful 

 instinct by which many birds, carried to a distance from^ 

 their homes, travel straight back again, is well known, as 

 exemplified by carrier-pigeons and other birds. 



The song of birds is, as a general rule, the ex- 

 pression of their delight at the season of pairing, 

 and is chiefly heard at that time ; though, in an artificial 

 state, by high feeding and warmth, it is often continued 

 through the year, and by some few birds, more or less so 

 even in the wild state. The chief families among whom this 

 charming faculty is developed most are the Merulidse, 

 Saxicoliu83, Sylviadas, Larks, and some Finches. A few 

 Shrikes and Flycatchers, and some Starlings have also 

 pretty songs. The female is believed in many cases to be 

 attracted to her mate by his song, and the cock nightingales, 

 and some other warblers, are said not to seek their mates, 

 which repair to the spot whence the song proceeds. The 

 call of the Cuckoo is probably for the same purpose. 

 During the season of love the attitudes assumed by many 

 birds are very remarkable, as in the case of the Cock 

 Bustard of India, and the European Bustard ; and the 

 well known display by the Peacock of his magnificent 

 train, and the seasonal plumage of the E-ufF, of the male 

 Leek Florikin, and of many other birds, are all intended to 

 fascinate and attract the females. Many birds are very 



