42 OUR SUMMER MIGRANTS. 



I have been familiar enough with birds in their 

 winter quarters, and have no hesitation in 

 asserting that migratory species (with the re- 

 markable exceptions named) do not even pair 

 until they have returned to their summer haunts. 

 Were they to do so, I could not but have 

 repeatedly noticed the fact, and must needs 

 have seen very many of their nests and young." 



To my suggestion that from Mr. Layard's 

 observation of young birds there, the Common 

 Swallow, H. rustica, probably breeds at the 

 Cape during the season that it is absent from 

 the British Islands, Mr. Blyth replied : 



" According to my experience of Hirundo 

 rustica (and I have had the best opportunities for 

 observation), it decidedly does not breed in its 

 winter quarters. Some birds of this species, 

 which pass their non-breeding season within the 

 tropics, may migrate south instead of north, and 

 breed in the summer of the southern hemi- 

 sphere instead of that of the northern hemi- 

 sphere ; but there is no reason to suppose that 

 they are the same individuals. Were it so, the 



