BIRDS 



293 



birds, for example the English sparrow, rear several Ijroods 

 of young a year, but most species have one or two. In 

 some species the male aids in buikling the nest and takes his 

 turn at sitting on the eggs, while in other species the 

 female does practically all of the work of rearing the young. 

 Nesting habits. — In Iniilding homes in which to deposit 

 eggs an( I rear the young, birds diffei- greatly. Perhajjs the 



Fig. 198. — Nest of a niuckijig bird 



least careful birds in these matters ar'e the auks. Some 

 of these l)irds drop their eggs on the i:>a.re ground oi- aiiKjng 

 the loose stones and rocks with no attempt at making any 

 nest whatever. The majority of birds, however, take great 

 care in Iniilding their nests and concealing them from 

 marauders. The Old World cuckoo and the cowbirds 



