FIELD BOOK OF INSECTS. 



carelessness on almost any vegetation near grape vines. 

 These eggs are washed by rains to the ground where the 

 larvce hatch and burrow into the earth searching for a 

 grape root in which to feed. The larval life lasts for 

 nearly two years, the first winter being passed naked in the 

 burrow and the second enclosed in a thin hibernaculum of 

 silk. This, however, is not the cocoon, for when spring 

 comes the larva works its way to near the surface of the 

 ground where it makes a tough cocoon of earth, excrement, 

 and silk within which it changes to a brown pupa with a 

 yellow-banded abdomen. About a month later (July or 

 August) the pupa comes half-way out of the ground and the 

 adult is freed. 



Bembecia 



This is the Raspberry Root-borer or 



Blackberry Crown-borer, both names in- 



marginata 



dicating the food habits of the larva, 

 while the generic name suggests the resemblance which 

 some of the adults of the genus bear to certain wasps 

 (Bembex). The female of this species has a wing expanse of 

 about 1.5 inches; the front wings are transparent except 

 for the brown margins, tips, and a band which crosses 

 each wing at about two thirds of the distance from the 

 base to the tips ; the hind wings are altogether transparent 

 (except, of course, for the veins and outer fringe which are 

 opaque in most, if not all, species) ; the abdomen is banded 

 with brownish-black and yellow, the former color pre- 

 dominating in front, the latter behind; the legs are largely 

 yellow. The male is somewhat smaller than the female 

 and his abdomen has less yellow at the hind end. The 

 moths emerge in, usually, late summer; the eggs are laid 

 on the canes close to the ground ; and the larvae, on hatch- 

 ing, crawl down the stem where they hibernate under 

 the bark just below the surface of the ground. In the 

 spring they start to bore into the roots or the base of the 

 plant, often girdling it. They spend the second winter 

 in their burrows and the following spring work upward 

 in the plant to a point above ground where, just inside the 

 bark, they pupate. About a month later the pupa cuts 

 the bark with its "horn," crawls partly out, and the 

 adult emerges to mate and start the history anew. 



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