The Leaf-Hoppers 



sunny places, is destructive to clover and attacks a great variety of 

 useful plants such as cabbage, celery, turnips, strawberry, beets 

 and many weeds. 



Typical Life History of a Leaf-Hopper 



( Deltocephalus inimicus.) 



This little leaf-hopper is one of the species which is com- 

 monly found in pastures and meadows. It has been reared upon 

 young wheat plants by Professor F. M. Webster. The females 

 laid their eggs in November in the tissue of the leaves and the 

 young could be seen developing within the eggs without removal. 

 They were especially noticeable just prior to issuing by their jet 

 black eyes. A few days after hatching the young leaf-hoppers 

 molted and they molted again twice thereafter, the full-grown 

 individuals making their appearance December 22d, giving a life 

 period of forty-one days from the egg to the adult. The species 

 seems to hibernate both in the egg state and in the adult condi- 

 tion and to have several generations each year. Osborn found 

 the eggs inserted under the skin of the leaves of blue grass, 

 making little blister-like swellings near the tips and causing them 

 to turn yellow. Those which hibernate in the egg state issue 

 in great numbers in grass lands early in May. There are at least 

 two generations each year, the young being numerous in late 

 May and in August and the adults in June and in the fall. Large 

 numbers have been seen attracted to the electric lights in Illinois. 

 (Forbes & Hart.) 



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