FEEDING OF THE YOUNG. 207 



even been proposed to have an act of parliament pro- 

 hibiting bird-catchers from exercising their art within 

 twenty miles of the metropolis ; and also prohibiting 

 wild birds of any kind from being shot or otherwise 

 caught or destroyed within this distance, under 

 certain penalties. It is very clear, however, that such 

 an act could never be carried ; and though it might 

 be advantageous to gardens, orchards, and farms, 

 yet the attacks which the same birds make on fruit 

 would probably be an equivalent counterbalance. 



In the case of swallows, on the other hand, it has 

 been well remarked by an excellent naturalist, that 

 they are to us quite inoffensive, while "the beneficial 

 services they perform for us, by clearing the air of 

 innumerable insects, ought to render them sacred and 

 secure them from our molestation* Without their 

 friendly aid the atmosphere we live in would scarcely 

 be habitable by man : they feed entirely on insects, 

 which, if not kept under by their means, would swarm 

 and torment us like another Egyptian plague. The 

 immense quantity of flies destroyed in a short space 

 of time by one individual bird is scarcely to be 

 credited by those who have not had actual experience 

 of the fact.'' He goes on to illustrate this from a 

 swift (Cypselus murarius, TEMMINCK), which was 

 shot. " It was in the breeding season when the 

 young were hatched ; at which time the parent birds, 

 it is well known, are in the habit of making little 

 excursions into the country to a considerable distance 

 from their breeding places, for the purpose of collect- 

 ing flies which they bring home to their infant 

 progeny. On picking up my hapless and ill-gotten 

 prey, I observed a number of flies, some mutilated, 

 others scarcely injured, crawling out of the bird's 

 mouth ; the throat and pouch seemed absolutely 

 stuffed with them, and an incredible number was at 

 length disgorged. I am sure I speak within compass 





