326 ARTICULATA: INSECTA. 



On the contrary, other hemiptera, as Cicadas, Plant- 

 lice, etc., have the wings of uniform thickness through- 

 out, and the wings do not lie flat upon the back, as in the 

 Hemiptera heteroptera ; and having wings of uniform 

 thickness throughout, they are called Hemiptera homop- 

 tera. 



Of the Hemiptera homoptera, few, if any, are more 

 interesting than the Cicadas or harvest-flies or Cicadidse. 

 These insects have a broad head, large eyes, and three 

 eyelets on the crown. Both pairs of wings are trans- 

 parent and distinctly veined. The males are furnished 

 with an apparatus by which they produce a loud buzzing 

 sound. 



This apparatus consists of a pair of organs which have been aptly 

 compared to a pair of kettle-drums one situated in each side of the 

 abdomen, and each formed of convex pieces of a parchment-like mem- 

 brane, finely plaited, and played upon by means of muscular fibres 

 fastened to the inside ; and thus, by the rapid contraction and relaxa- 

 tion of these fibres, the drum-heads are alternately tightened and 

 loosened, and the sounds above-named produced. 



The female Cicadas are provided with a piercer for 

 perforating the limbs of trees, in which they lay their 

 eggs. This piercer consists of three pieces two outer 

 ones, which are grooved on the inside, and toothed on the 

 outside like a saw, and a central piece, which is a sort of 

 spear-pointed borer, which moves freely between the 

 other two. 



The Greeks, we are told, often kept these insects in 

 cages that they might enjoy their " music." And the 

 Greeks also used them as food, eating both the pupae and 

 the perfect cicadas. 



Our common species are the Dog-day Cicada or Harvest- 

 fly (Cicada eanicularis, Harris) and the seventeen-year 



