78 FARM FRIENDS AND FARM FOES 



autumn, the strange, shrill noise of the common Harvest 

 Fly, or Dog-day Cicada. This insect is present everywhere, 

 and its curious song is one of the most striking and charac- 

 teristic of summer sounds. 



The most famous member of this family, however, is the 

 strangely interesting Periodical Cicada or Seventeen-year 

 Locust. The adults of these insects appear in certain lo- 

 calities at intervals of either thirteen or seventeen years. 

 They may then be exceedingly numerous. At such times 

 they deposit eggs in the twigs of trees. These eggs soon 

 hatch into strange little larvae that drop to the ground and 

 work their way through the soil until they find some roots 

 of trees or shrubs. Here they remain feeding and growing 

 very slowly for a long period of years. As already indi- 

 cated, in some regions they complete their development in 

 thirteen years and in others in seventeen years. By the 

 end of this long time, the little larvae have become quite 

 large, and are of the shape shown in the lower illustration 

 on the next page. They now come to the surface of the 

 soil and crawl up the trunk of some tree or shrub, where 

 they emerge as adult cicadas. These are able to make a 

 curious shrill noise, somewhat similar to that of the Dog- 

 day Cicada, although in both species the ability to sing is 

 confined to the males. When the insects are very abun- 

 dant, the sound may become almost deafening. 



LEAF HOPPERS 



If with a close-meshed insect net, you sweep diligently 

 a few yards of meadow or pasture land, it is probable that 

 the most abundant insects you find in the net will be the 

 small, flattened, quick-jumping Leaf Hoppers (Jassoidea). 

 These insects vie with the plant lice in their enormous 

 numbers. They are likely to be present in any region. 



