BRITAIN'S BIRDS AND THEIR NESTS. 249 



the family is the large, hard, conical beak. This is an 

 adaptation to a diet consisting chiefly of seeds. Insects, 

 however, are taken in summer by most species to a greater 

 or less extent, and the young in the nest are usually fed 

 entirely on them. In search of seeds Finches have to 

 spend much of their time on the ground, where they 

 progress by hopping ; but othei'wise they are typical 

 ' perchers.' In summer they are scarcely gregarious ; but 

 in winter they habitually pack together, the sexes very 

 often keeping in separate flocks. No very high develop- 

 ment of song is characteristic of the group, most of the 

 birds possessing short refrains of stereotyped pattern and 

 little musical merit. To this, however, there are several 

 brilliant exceptions. The song is to be heard almost 

 throughout the year in fine weather, although, of course, 

 most regularly in spring and early summer. About the 

 end of summer, however, there is a short period of almost 

 complete silence. This corresponds with the occurrence 

 of the annual moult, always a time of depression and low 

 vitality. 



The song of the Greenfinch is certainly not one of the 

 exceptions, being very feeble. The call-note is very char- 

 acteristic, a long-drawn-out ' schweezo "* ; and the alarm 

 is a plaintive ' tewy.' The female and immature birds 

 of both sexes are very much duller than the adult male. 



The Greenfinch, or ' Green Linnet,' is resident in the 

 British Isles wherever plantations of trees are to be found. 

 The increase of these in some parts has led to a recent 

 slight extension of the breeding range, which now includes 

 Orkney, for instance. The species is also abundant as an 

 autumnal immigrant on our eastern seaboard. 



The Greenfinch shows no marked degree of ability as 

 a nest-builder, the cup-shaped structure of roots, moss, 

 and the like being generally rather ill-built. It is lined 



2f 



