The Decticus: his Instrument 



the Cricket, her near neighbour. Let us first 

 listen to the White-faced Decticus. 



The performance begins with a hard, 

 sharp, almost metallic sound, very like that 

 emitted by the Thrush keeping a sharp look- 

 out while he stuffs himself with olives. It 

 consists of a series of isolated notes, tick- 

 tick, with a longish pause between them. 

 Then, with a gradual crescendo, the song 

 develops into a rapid clicking in which the 

 fundamental tick-tick is accompanied by a 

 continuous droning bass. At the end the cre- 

 scendo becomes so loud that the metallic 

 note disappears and the sound is transformed 

 into a mere rustle, a frrrr-frrrr-frrrr of the 

 greatest rapidity. 



The performer goes on like this for hours, 

 with alternating strophes and rests. In calm 

 weather, the song, at its height, can be heard 

 twenty steps away. That is no great di- 

 stance. The noise made by the Cicada and 

 the Cricket carries much farther. 



How are the strains produced? The 

 books which I am able to consult leave me 

 perplexed. They tell me of the " mirror," 

 a thin, quivering membrane which glistens 

 like a blade of mica; but how is this mem- 

 brane made to vibrate? That is what they 



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