The Locusts: their Organ of Sound 



might, one would think, acquire wings, that 

 higher mechanism of locomotion. 



Rapid flitting from crest to crest, over the 

 valleys deep in snow; easy flight from a 

 shorn pasture to one not yet exploited: can 

 these be negligible advantages to the Pedes- 

 trian Locust? Obviously not. The other 

 Acridians and in particular his fellow- 

 dwellers on the mountain-tops possess wings 

 and are all the better for them. What is 

 his reason for not doing as they do? It 

 would be very profitable to extract from 

 their sheaths the sails which he keeps packed 

 away in useless stumps; and he does not do 

 it. Why? 



" Arrested development," says some one. 



Very well. Life is arrested half-way 

 through its work; the insect does not attain 

 the ultimate form of which it bears the em- 

 blem. For all its scientific turn of phrase, 

 the reply is not really a reply at all. The 

 question returns under another guise : what 

 causes that arrested development? 



The larva is born with the hope of flying 

 at maturity. As a pledge of that fair future, 

 it carries on its back four sheaths in which 

 the precious germs lie slumbering. Every- 

 thing is arranged according to the rules of 



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