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perfect state it is a little four- winged fly, of a jet-black 

 color, except the thorax, or part of the back between 

 the wings, which is red, and the legs, which are varie- 

 gated with pale yellow. The body of the female 

 measures one quarter of an inch in length, that of the 

 male is somewhat shorter. Small and apparently 

 innocuous as these insects are, each pair may become 

 the progenitors of forty or fifty destructive larvae. The 

 flies rise from the ground in the spring, not all at one 

 time, but at irregular intervals, and deposit their eggs 

 beneath the terminal leaves of the vine. The larvae, 

 unlike those of the saw-fly of the cherry-tree, are long 

 and cylindrical, resembling caterpillars ; they feed in 

 company, side by side, beneath the leaves, each fra- 

 ternity consisting of a dozen or more individuals. 

 Commencing upon the first leaf, at its edge, they 

 devour the whole of it, then proceed to the next, and 

 so on successively down the branch, till all the leaves 

 have disappeared, or tiU the insects have reached 

 their full size. They then average five eighths of an 

 inch in length ; the head and tip of the tail are black, 

 and the body is pale green, with transverse rows of 

 minute black points. Having finished the feeding state, 

 they leave the vine, enter the earth, form for them- 

 selves small oval cells, change to pupae, in due dme 

 emerge from the earth in the perfect state, and lay 

 their eggs for a second brood. The larvae of this 

 second brood are not transformed to flies until the 

 ensuing spring, but remain torpid in their earthen cells 

 through the winter. During the present summer many 

 vines have been entirely stripped of their leaves by 

 these insects, and the evil seems evidently on the 



