8 COLIN CLOUT'S CALENDAR. 



t|uarters in Algeria by the sun and the flowers, flying 

 low above the gorse and the violet-beds in the undercliff, 

 where they may now catch hundreds of small insects 

 on the wing around the honey-bearing blossoms which 

 attract them out of their cocoons upon these warmer and 

 brighter mornings. 



What marvellous complexity of interaction and 

 mutual relations between all the parts of nature and 

 organic life this familiar fact of the swallows' yearly 

 return implies for us ! Hard-billed seed-eating and 

 berry-eating birds, or mixed seed-eaters and insect-eaters, 

 can manage to find food for themselves in England all 

 I he year round. Nay, even those species which live 

 mainly upon worms, slugs, and other hardy small deer, 

 can pick up a living somehow or other through our 

 northern winters. But pure fly-catchers, like the 

 swallows, must starve during the five months when 

 winged insects are almost wholly lacking in temperate 

 climates. Thus it becomes a matter of necessity with 

 them to move south at the beginning of autumn, towards 

 the orange groves of Italy and the palms of Africa, 

 lieforc they can return, there must be insects in the 

 north ; and these insects must have been hatched from 

 the egg, and re-hatched from the chrysalis stage, before 

 they are fitted to become food for swallows, since swallows 

 feed only on the wing. Accordingly, it is not until the 

 spring flowers are well out, and the winged insects have 

 begun to suck their honey, that the various species of the 

 swallow family make their appearance. 



The true swallows come first, and, taking one year 

 with another, the second week of April may be taken as 

 the average date of their return to the south-western 



