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SUMMARY. 
is louse makes its appearance only in spring, and attacks cu- 
taceous plants generally, soon after they commence to grow, 
times killing them at once. It continues its depreciations upon 
pecies of this order until frost kills the vines in fall, but prefers 
i melons to watermelons, and the latter to cucumbers. A root- 
also occurs, but with unknown effect. The species is subject 
e attacks of the usual enemies, which greatly interfere with its 
li ^es, and often suspend them. The eggs are laid in autumn, 
ibly apparently by preference upon the same ground where the 
s developed. It is therefore prudent to destroy the old vines, 
;o avoid planting melons, cucumbers and squashes upon the same 
id two years in succession. 
ad dust, pyrethrum powder, tobacco smoke blown under the edge 
sheet or canvass covering, a weak mixture of kerosene and 
: (not over one part to twenty) are all more or less effective 
beir artificial destruction; but if their natural enemies are seen 
very numerous, the probabilities are that the lice have about 
lj led their course for the season and had better be left unmo- 
11. Whatever artificial application is made, care should be taken 
ake the vines and leaves to drive away the winged parasites, 
1 might otherwise be sacrificed with their hosts. 
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