15 



These parasites are day-flies, and as they resemble flies it follows 

 that the birds commonly called "fly-catchers" — especially the Swal- 

 lows — are instrumental to a certain degree in their destruction. The 

 Swallows have for many years held a very conspicuous place among 

 the birds which the law protects, owing, no doubt, to the fact that 

 they have never been known to feed upon grain or seeds of any 

 kind. It is my opinion, however, that they are not so beneficial as 

 they are supposed to be. In the first place, as they are on the 

 wing only in the day time, it is evident that they do not catch very 

 many of the really injurious insects, such as the parents of the 

 Army Worm, Canker Worm, etc., which are never on the wing in 

 the day time, except when disturbed. 



The Swallows are commonly supposed to feed upon flies, the ma- 

 jority of which cannot be said to be very injurious to the agricul- 

 turist. In their early stages many flies live in excrementitious 

 matter, thus aiding in removing this filth out of the way. Those 

 flies which infest our houses are usually looked upon as decided 

 nuisances ; yet it is evident that the Swallows catch but few of 

 these. The flies that are so troublesome to horses and cattle are 

 no doubt caught in large numbers by these birds. But as nearly all 

 the internal parasitic insects resemble flies — and these insects are 

 far more beneficial than any other kind — and as the greater number 

 of them are day-flies, it is very probable that they form the prin- 

 cipal diet of the Swallows. 



Now it is very evident that the Swallows were designed to keep 

 these parasites from becoming so numerous as to utterly annihilate 

 the species of insect which they infest ; but as Man has constantly 

 waged war against the birds of prey which were intended to keep 

 the Swallows in check, it very naturally follows that the Swallows 

 will, in time, become so numerous as to so far annihilate the para- 

 sites of many insects as to allow the insects to become excessively 

 multiplied. This is no doubt the reason that many insects become 

 so numerous as to attract universal attention. 



I do not advocate the complete annihilation of the Swallows, but 

 have merely given the facts in the case, so that our agriculturists 

 may be enabled to judge for themselves the position which these 

 birds ought to occupy. 



REMEDIES. 



Where the Greater Leaf-rollers appear in limited numbers they 

 may be destroyed by crushing them with gloved hands while in their 

 cases, but when they appear in destructive numbers it will be neces- 

 sary to employ some other method. In such cases the infected 

 trees may be sprinkled with a solution of London Purple or Paris 

 Green and water, as recommended for the Yellow Canker Worm. 



