318 



NOISES OF INSECTS. 



As I have nothing to communicate to you with respect to 

 the love-songs of other insects, my further observations will 

 be confined to the tribes lately mentioned, the Gryllina, &c, 

 and the Cicada. 



No sound is to me more agreeable than the chirping of 

 most of the Gryllina, Locustina, &c. ; it gives life to solitude, 

 and always conveys to my mind the idea of a perfectly happy 

 being. As these creatures are now very properly divided 

 into several genera,, I shall say a few words upon the song of 

 such as are known to be vocal, separately. 



The remarkable genus Pnumora — whose pellucid ab- 

 domen is blown up like a bladder, on which account they are 

 called Blaazops by the Dutch colonists at the Cape — in the 

 evening, for they are silent in the day, — make a tremulous 

 and tolerably loud noise, which is sometimes heard on every 

 side. 1 The species of this genus have a claim to the name of 

 Fiddlers since their sound is produced by passing the hind- 

 legs, which are furnished with a series of smooth elevated 

 ridges, and may be called the fiddlesticks, over a number of 

 short transverse elevated ridges, of a similar though slightly 

 different structure, on the abdomen, which may be called the 

 string sp- 



The cricket tribe are a very noisy race, and their chirping 

 is caused by the friction of the cases of their elytra against 

 each other. For this purpose there is something peculiar in 

 their structure, which I shall describe to you. The elytra of 

 both sexes are divided longitudinally into two portions; a 

 vertical or lateral one, which covers the sides ; and a hori- 

 zontal or dorsal one, which covers the back. In the female 

 both these portions resemble each other in their nervures ; 

 which running obliquely in two directions, by their intersec- 

 tion, form numerous small lozenge-shaped or rhomboidal 

 meshes or areolets. The elytra also of these have no elevation 

 at their base. In the males the vertical portion does not 

 materially differ from that of the females ; but in the hori- 

 zontal the base of each elytrum is elevated so as to form a 

 cavity underneath. The nervures also, which are stronger 

 and more prominent, run here and there very irregularly 



1 Span-man, Vay. i. 312. 



2 Charpentier in Silbermann's Revue Entom. iii. 314. 



