THE PERIODICAL CICADA 



earthly form for that of a winged insect of the upper world 

 and sunshine, though the skins ordinarily seen are those of 

 the annual species. 



The cicada undergoes a striking transformation from 

 the young to the adult, but it does so directly and not by 

 means of an intervening stage, or pupa. The young of 

 an insect that transforms directly is termed a nymph by 

 most American entomologists. The last nymphal stage 

 is sometimes called a "pupa," but it is not properly so 

 designated. 



The life of the periodical cicada stirs our imagination 

 as that of no other insect does. For years we do not see 

 the creatures, and then a springtime comes when countless 

 thousands of them issue from the earth, undergo their 

 transformation, and swarm into the trees. Now, for 

 several weeks, the very air seems swayed with the mo- 

 notonous rhythm of their song, while the business of ma- 

 ting and egg-laying goes rapidly on; and soon the twigs of 

 trees and shrubs are everywhere scarred with slits and 

 punctures where the eggs have been inserted. In a few 

 weeks the noisy multitude is gone, but for the rest of the 

 season the trees bear witness to the busy throng that so 

 briefly inhabited them by a spotting of their foliage with 

 masses of brown and dying leaves where the punctured 

 stems have broken in the wind. The young cicadas that 

 hatch from the eggs later in the summer silently drop to 

 the earth and hastily bury themselves beneath the sur- 

 face. Here they live in solitude, seldom observed by 

 creatures of the upper world, through the long period of 

 their adolescent years, only to enjoy at the end a few 

 brief weeks of life in the open air in the fellowship of 

 their kind. 



The Nymphs 



Of the underground life of the periodical cicada we 

 still know very little. The fullest account of the history 

 of this species is that given by Dr. C. L. Marlatt in his 



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