312 BRITAIN'S BIRDS AND THEIR NESTS. 



The Blackbird and the Ring-Ousel form a subdivision 

 of the Thrush genus, and are characterised by the dark- 

 ness of their plumage. Another notable point is the 

 difference in plumage shown by the adult male and 

 female. Anything considerable in this way is exceptional 

 in the Thrush family, in contrast to the Finch group, 

 where great diversity is the rule. 



The Blackbird is now abundant in every part of the 

 British Isles except a few of the bleakest islands and 

 districts, but its spread into some of the most northern 

 and western regions is of comparatively recent date. 

 Some southward emigration and a great deal of immi- 

 gration from north-western Europe occur in autumn, with 

 corresponding return journeys in spring. 



Bushes, hedges, low trees, piles of cut sticks, &c., are 

 the nesting situations of the Blackbird. The nest has 

 a lining of dry grass instead of mud, but otherwise 

 resembles that of the Thrush. The four to six effg-s 

 have reddish-brown flecks thickly strewn on a greenish- 

 blue ground. Unmarked eggs are sometimes seen, and 

 a nest containing a proportion of such eggs has been 

 found at the same spot for several successive years. 

 Two inferences may be drawn : first, that an individual 

 bird tends to lay eggs of the same type ; second, that 

 the same hen Blackbird returns to the same place for 

 several seasons. Unfortunately we do not know the cock's 

 movements ; it may well have been the same pair all the 

 time. But one would like to know whether it is the 

 male or the female that determines the nesting locality 

 in the case of a newly ' matched ' pair. 



The cock Blackbird is a fine songster and a good 

 mimic. The loud, cackling alarm-cry of the species is 

 well known. A characteristic trait, also, is the sharp 

 uptm-ning of the long tail at the moment of alighting. 



