PACKAKD] INSECTS OP THE GARDEN". 55 



Mr. C. S. Miuot, in an interesting article entitled "Cab- 

 bage Butterflies," in the "American Entomologist," vol. 2, 

 strongh^ recommends destroying the chrysalis, which may be 

 found under chips, boards, stones, etc., and advises that 

 boards, raised two inches above the surface of the ground, 

 be placed among the plants to attract the caterpillars when 

 about to change to a chrysalis. 



Mr. Curtis has described and figured several parasites of 

 the three species of cabbage butterflies found in England, 

 and he shows how thoroughlj^ they keep in check these trou- 

 blesome worms. Certain minute ichneumon flies (Chalcids) 

 lay their eggs in those of the butterflies. Another Chalcid 

 fly (Pteromalus brassicce) lays its eggs on the outside of the 

 chrysalis of the "White Cabbage Butterfly (Pieris brassicce), 

 and sometimes two or three hundred of the little Chalcid 

 maggots have been found living riotously within a single 

 chrysalis. They turn into minute brilliant flics, which mul- 

 tiply in excessive quantities. Mr. Curtis remarks that 

 "some species of this extensive genus (PieromaZws), prob- 

 ably comprising nearly one thousand species ( ! ) swarm even 

 in our houses, especiady in the country, where in October 

 and November I have seen immense numbers inside of the 

 windows, and I believe that they hibernate behind the shut- 

 ters, in the curtains, etc." 



Fortunatelj'' for the prospects of American gardeners, we 

 have a parasite (Fig. 44 a, male ; 6, female ; c, larva ; d, pupa) 

 which already carries off large numbers of the caterpillar. 

 Lately, in the middle of September, Mr. F. W. Putnam 

 handed me one hundred and ten chrysalides of the butterfl}-, 

 all l)ut two of which wore infested by these parasites in both 

 the larval and pupa states ; while from other chrysalides 

 the adult Chalcid flies were emerging. They continued to 

 emerge until late in the autumn. The infested chrysalides 

 of tlie butterfly could l)e easily distinguished by the livid and 

 otherwise discolored and diseased appearance of the body, 



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