5i6 Bulletin 78. 



few puparia early in April, and yet the flies appeared in large 

 numbers three weeks later. These facts would indicate that 

 many of the flies hibernated. It is not at all improbable that the 

 flies do pass the winter secreted in crevices or under rubbish, etc. 

 However, there is need of further evidence on this point. 



NATURAL ENEMIES OF THE PEST. 



This pest, like many other insect pests, has several enemies 

 among the animals, including those of its own kind — the insects. 

 These natural enemies help to hold this pest in check, but the 

 balance of nature has not yet reached that point where the scale 

 tips in favor of the enemies. However, they are worthy of con- 

 sideration, for the time may come when they will eSectually 

 check it. 



Of the larger animals, two are recorded as feeding on the mag- 

 gots. In the Cotintry Gentlemayi for 1864, a correspondent is 

 advised to turn his chickens into his cabbage patch to destroy 

 the maggots. At one end of our experiment plot on Long 

 Island, chickens injured some of the plants soon after they were 

 set out. Later, when the maggots had appeared in full force, 

 the chickens found them, and thousands of them were eaten, but 

 usually the plants were also either pulled up or badly damaged. 

 Thus, on the whole, it is hardly advisable to try to fight this 

 pest with chickens, unless the plants are already beyond recovery. 



In England, as Miss Ormerod reported in 1884, the Rooks 

 sometimes tear up infested plants and hardly a maggot escapes 

 them. 



Several insects have been recorded as enemies of the Cabbage 

 Root Maggot and allied insects. 



In Europe, five different species are recorded as parasites on Anthorayiians. 

 In 1834, Bouche enumerated the following: Alysia ruficeps, from the 

 pupae of Anthomyia radicunt ; Alysia manducator, from the pupae of 

 Athomyia deniipes ; Microo;asler anthomyiariiin, from the larvae of Phnbia 

 ceparum ; Figites anthomyiarum, from the pupae of several species of 

 Anthomyia, as dentipes, Jloralis {=brassiccs), etc. Tascbenberg says : 

 "The small Braconid Opius procerus Wsml. was bred from the larvae by 

 Mr. Brieschke." All of these insects are minute active wasp-like forms, 

 which doubtless crawl into the earth among the maggots and sting their 

 eggs into the bodies of their helpless victims. 



