British Birds, their Nests and Eggs. 127 



pretty wild pigeons, nests in colonies in rabbit- 

 burrows, as does the brown owl. When 

 ferreting for rabbits the writer has put both 

 these birds out of the holes instead of their 

 rightful owners. The nuthatch is yet another 

 bird which upholds the same rule, and whose 

 case is peculiarly interesting. It not only lays 

 purely white eggs in holes in trees, but if the 

 hole for ingress and egress is one whit too large 

 it is plastered up by the industrious bird until 

 it barely admits the body of the clever little 

 architect. 



The cuckoo is quite a Bohemian among birds, 

 and it is doubtless owing to its vagrant habits 

 that there yet remain several points in its life- 

 history which have to be cleared up. The most 

 interesting of these questions are those which 

 relate to its nesting and nidification. It was 

 once thought that the cuckoo paired, but it is 

 now known that the species is polygamous. The 

 number of hens that constitute a harem is not 

 known, but from the number of bachelor birds 

 the males must greatly predominate over the 

 females. Dissection conclusively proves that 

 each female lays a series of eggs, and that these 

 occur in the ovary in widely different stages of 

 maturity. The older naturalists thought that the 

 cuckoo laid its eggs actually in the nests of other 

 birds, but it is now known that it conveys them 

 thither in its bill. The egg of the cuckoo has 



