192 Bulletin 157. 



the leaves of the vine also serve as food for the earlier or grub- 

 stage of the insect. Sometimes considerable damage is done by 

 these grubs or larvae. It is very important that grape growers 

 should also be able to recognize the grubs, for most of the dam- 

 age which the insect might do the succeeding season could be 

 averted by killing them. The little dark-brown grubs, shown 

 natural size at work in figure 1 1 , begin to appear on the leaves 

 during the latter part of May and are at work during the most of 

 June in New York. When full grown the grubs measure from 

 7 to 9 mm. (.275 to .354 inch) in length. They have the six 

 true legs typical of insects, and also one fleshy, yellowish false 

 or pro-leg on the anal segment. They are of a dark yellowish- 

 brown (nearly Ridgeway's raw umber) color, lighter and more 

 yellowish on the venter ; the younger grubs are considerably 

 darker in color. The head and thoracic legs are shining black, 

 while the thoracic and anal shields are not quite so densely black 

 in color. The body is marked with regular rows of blackish 

 spots, each bearing a short hair ; the size and arrangement of 

 these spots is well shown in figure 13. Fortunately these little 

 brown grubs usually work on the upper side of the leaf so that, 

 although the}' are only a little more than a quarter of an inch in 

 length, they are easily found by children's sharp eyes. 



In the other two stages of its existence — the egg and the 

 pupa — this flea-beetle does no damage. These stages are illus- 

 trated and discussed in telling the life-story of the insect. 



Its Name. 



When this flea-beetle was first described nearly a centur}^ ago 

 it was given the very apt scientific name of chalybea ; this word 

 means ' ' steel-blue, ' ' the usual color of the beetle. Dr. Harris, in 

 discussing the insect in 1841, popularized this name into "the 

 steel-blue flea-beetle, "and also suggested that it might be called 

 ' ' the grape-vine flea-beetle ' ' on account of its habits. Both of 

 these popular names are now in common use. and the former has 

 been shortened by many grape-growers to " the steely-bug" or 

 '.' steely-beetle. " All of these names are very apt and suggestive 

 and we are not sure that the more appropriate one has been 

 chosen for the title of this bulletin. 



