Ichneumon Flies 



seasons a larger number than usual may escape, and 

 then we have a butterfly year, but the relentless 

 ichneumon flies soon restore the balance. They, too, 

 have their young to provide for, and a strange mode 

 of existence they have. Once you get to know these 

 ichneumons at sight, you will be astonished at the 

 number of them. All the summer through you will 

 find them hawking about the trees, bushes, nettles, and 

 heather, and, indeed, wherever larvae are to be found, 

 there, too, you will find these flies. There are many 

 species of them. Once a female has discovered a larva 

 its doom is sealed. The ordinary larva has very few 

 defensive weapons ; he may wriggle and squirm and 

 look terrifying, but all the same the ichneumon sets 

 about her task of placing one or two, and in many cases 

 a dozen or two, of her eggs either upon or under his 

 skin. These eggs soon hatch, and the little white 

 maggots pass their existence inside the doomed creature, 

 eating all the tissues away, at first avoiding the vital 

 organs, which they leave until the last. When they 

 have reached their allotted span, and are about to change 

 to the pupa state themselves, they soon finish off their 

 victim, and all that remains of what might have been a 

 brilliant butterfly is a little shrivelled bit of skin and a 

 host of little or it may be a few big black, brown, 

 or grey flies. Sentiment apart, these parasitic flies are 

 extremely useful. When you consider the large number 

 of eggs laid by a single female butterfly or moth from 

 two to six hundred is a fair average you will realize 

 that if this enormous progeny were to survive and go 

 5 



