l62 



THE POPULAR SCIENCE MONTHLY, 



The next most efficient aid in the destruction of the leaf-lice is 

 found among the lace-wing flies, one species of which, more especially, 

 viz., the Weeping Lace-win^ [Chrysopa plorabu7ida Fitcli), I find 

 very frequently within the galls, devouring their contents. These 



Fig. 1, 



Thrips. 



flies are known as well by their brilliantly golden eyes as by the pe- 

 culiarly ofiensive odor, as of human ordure, which some of them emit. 

 The eggs are adroitly deposited (Fig. 2, a) by the parent at the tips 

 of long silk-like stalks, in order to prevent first-born larvae from exer- 



FiG. 2. 



a b c (i 



LACE--WING Fly.— a, eggs ; 6, larva ; c, cocoon ; d, fly, the wings to ihe left omitted. 



cising their cannibalistic propensities on their yet unborn brethren. 

 The larva (Fig. 2, b) is very rapacious, and, when ready to transform, 

 winds itself up into a wonderfully small cocoon (considering the size 

 of the insect which makes it and which issues from it), which is spun 



Fig. 3. 



Fig. 4. 



Convergent Ladybird ; a larva, pupa, and beetle. 



Syrphus Larva. 



from the extremity of the body, and from which it issuef, when about 

 to acquire wings, through a neatly-cut, circular aperture. Next in or- 

 der, as Phylloxera enemies, may be mxcntioned the Ladybirds ( Cocci- 



