I 24 Cockroaches, Locusts, Grasshoppers, and Crickets 



keep up the chorus. At home, in house and garden, the domestic cricket 

 offers its music to the already over-full ears. All this choiring is done by 



singers without a voice; that is, without the 

 production of sound from the throat and 

 mouth by means of vocal cords set into vi- 

 bration by air. Insects are orchestral per- 

 i'ormers, using their legs and wings, for the 

 most part, to make their music. When the lo- 

 cust sings while at rest, it is rasping the inner 

 surface of the broad hind thighs across the 

 roughened outer surface of the folded fore 

 wings; when it "clacks" in the air, it is strik- 

 ing the front margin of the hind wing back 

 and forth past the hinder margin of the 

 thickened fore wings. When the cricket 

 shrills on the hearth, or anywhere else, he, for 

 only the male crickets have the musical gift, is holding 

 his fore wings uj) over his body at an angle with it of 

 about 45° and is rubbing together the upper surfaces of 

 the basal region of the fore wings, which are specially 

 modifirtl for this purpose. The tree-crickets, katydids, 

 and meadow green grasshojjpers have, in the males, 

 the same general sort of music-making apparatus as 

 the cricket, and sing by similarly rasping or rubbing 

 together the modified parts of the fore wings. This 



Fig. 155. — Longitudinal section through head and neck of locust, 

 showing disposition of alimentary canal, brain, and sub- 

 oesophagcal ganglion. (.-Vfter Snodgrass; much enlarged.) 



music-making by rasping is called stridulation, and for the most part 

 in.sect stridulation is strictly strident, and sounds to better advantage in the 

 field than it would from caged songsters in the parlor. 



