INSECTS 



or otherwise disturbed, the small males utter a succession 

 of sharp chirps very suggestive of the notes of some 

 miniature wren angrily scolding at an intruder. Never 

 does the small form of the cicada utter notes having the 

 burr tone of those of the larger species, and the vocal 

 differences of the two varieties are strikingly evident 

 when several males of both kinds are caged together. 

 When disturbed, each produces his own sound, one the 

 burr, the other the chirp; and there is never any sugges- 

 tion of similarity or of gradation between them. 



Egg Laving 



The cicadas lay their eggs in the twigs of trees and 

 shrubs and frequently in the stalks of deciduous plants. 

 They show no particular choice of species except that 

 conifers are usually avoided. 



The eggs are not stuck into the wood at random, but 

 are carefully placed in skillfully constructed nests which 

 the female excavates in the twigs with the blades of her 

 ovipositor (Plate 8). These nests are perhaps always 

 on the under surfaces of the twigs, unless the latter are 

 vertical, and usually there are rows of from half a dozen 

 to twenty or more of them together. 



Egg laying begins in the early part of June, and by 

 the tenth of June it is at its height. The female cicadas 

 can easily be watched at work, taking flight only from 

 actual interference. They usually select twigs of last 

 year's growth, but often use older ones or green ones of 

 the same season. In the majority of cases the female 

 works outward on the twig; but if this is a rule, it is a 

 very loosely observed one, for many work in the opposite 

 direction. 



Each nest is double; that is, it consists of two chambers 

 having a common exit, but separated by a thin vertical 

 partition of wood ( Plate 8, D, F). The eggs are placed 

 on end in the chambers in two rows, with their head ends 



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