PAIRING. 



themselves, as they must do, in the best situation 

 they can discover. 



Black-cap. 



The continuance of a nest in the same spot for 

 several years is more remarkable in the case of 

 migratory birds than in that Of magpies, which do 

 not migrate, and seldom go to any considerable dis- 

 tance frOm their breeding trees. There has been in 

 a garden adjacent to ours, the nest of a black-cap 

 (Sylvia atricapilla) for a succession of years, and 

 broods have been successively reared there, without 

 any observable increase in the population of the 

 species. Yet this bird, which is little bigger than a 

 wren, weighing only half an ounce, has to traverse 

 annually the whole of the south of Europe, and pro- 

 bably a great proportion of the north of Africa, ex- 

 posed of course to numerous accidents, as well as to 

 occasional scarcity of its appropriate food. From 

 the regular annual restoration, however, of this nest 

 at the same spot, it is obvious that one, if not both of 



