THE INSECT WORLD. 



93 



been treated at great length in the reports of the U. S. Entomo- 

 logical Commission and of the U. S. Department of Agriculture, 

 and these must be consulted : the methods discussed and recom- 

 mended are too numerous for reference here. In the invaded 

 regions fall plowing to destroy the eggs and the use of the 

 "hopper-dozers" on the young are indicated. 



Under some circumstances, when the number of grasshoppers 

 is not too great, they may be destroyed, or a large measure of 

 protection may be secured, by tempting them with poisoned 

 bran, of which they seem to be rather fond. It should be com- 

 posed of bran and Paris green, at the rate of one part of Paris 

 green to hfty by weight of bran, thoroughly moistened with 

 sugar water. Cabbage patches can often be protected in this 

 way against grasshoppers that come from uncultivated land, and 

 there are other cases where such a measure is of value. Indi- 

 vidual judgment must determine those cases. 



The LocustidcB are "long-horned grasshoppers," "meadow 

 grasshoppers," and "katydids," distinguished at once by very 

 long, slender antennae, rarely shorter than, and usually much 

 exceeding, the body. They are green in color as a rule, with 

 slender legs and thin wings, and we find them a vast array of mu- 

 sicians, — always the males only, — the sound-producing structure 

 occupying a triangular area at the base of the fore-wings, where 

 they overlap. Here one or more of the 

 veins is elevated and ridged on each wing, 

 and by rubbing these ridged surfaces to- 

 gether a strident sound is produced, in- 

 tensified by a membrane tightly stretched 

 between them. The pitch and volume of 

 the ' ' song' ' are regulated by the develop- 

 ment of veins and membrane as well as of 

 the tegmina, no two species being alike in 

 this respect. Special students of the family 

 soon learn to recognize the sounds made 

 by the different species as certainly as or- 

 nithologists know birds by their song. The 

 ears through which the songs appeal to the courted females and 

 competing males are situated on the fore tibiae, and are essentially 

 like the same organs found on the abdomen of the Acridiidcr. 



Fig 



Overlapping porlion of 

 the base of the wing in Cono- 

 cephalus, showing the ridged 

 veins and sound-producing 

 organ. 



