MUSIC 



319 



very different ; that of the left one, which bears the file, being 

 similar in texture to the rest of the wing-cover, while the Corre- 

 sponding part of the other tegmen is 

 rigid and transparent, and greatly 

 distorted, so as to create a cavity 

 which, no doubt, improves the sound ; 

 the scraper too is very perfectly 

 formed. The difference between this 

 form of musical organ and that of 

 L. viridissima is curious, inasmuch 

 as in the better instrument the im- 

 portant modifications are confined to 

 one tegmen, while in the other form 

 both tegmina are largely changed. 

 The difference appears to be that in 

 Locusta the left tegmen, as well as 

 the right one, acts as a sounding- 

 board, while in Mecopoda it does not 

 do so, but when the wings are closed 

 quite covers and conceals the musical 

 instrument. 



The Locustidae, notwithstanding 

 the fact that their alar organs are 

 generally more ample than those of the 

 Acridiidae, seem to be, as a rule, of more sedentary habits, and more 

 nocturnal in their activity. The musical powers of the different 

 species are very varied. Locusta viridissima produces a shrill and 

 monotonous but not disagreeable, sound, and is capable of sustain- 

 ing it for a quarter of an hour without any intermission, except 

 a break for the sake of starting again immediately with greater 

 force, like a performer on a flute. It occasionally chirps in the 

 day, but the act is then very brief. Bates informs us that one 

 of these singing grasshoppers, called Tanana by the natives 

 of the Amazon valley, is much admired for its singing, and 

 is kept in little cages. The Amazonian naturalist thought the 

 music of this species superior to that of any other Orthopterous 

 Insect he had heard. The name of this grasshopper is Thliboscelus 

 camellifolius. It is very similar in appearance to Cyrtoplnjllus 

 crepitans, the Insect we have represented in Fig. 187. 



The most notorious of the musical Locustids are the Katydids 



195. Inner face of base of 

 tegmina of Locusta, viridissima : 

 A, the two wing -covers separ- 

 ated ; B, in natural position with 

 mesouotum connecting them, 

 showing file and edge scraping 

 it ; a, the stridulating file ; b, 

 the rudimentary file on other 

 tegmeu. 



