HEMIPTERA. 401 



All the insects of this section feed exclusively on vegetable juices. The 

 females are provided with a scaly ovipositor, usually composed of three den- 

 tated blades, and lodged in a groove with two valves. They use it as a saw to 

 produce openings in plants in which they deposit their eggs. The last insects 

 of this section experience a sort of complete metamorphosis. 



I will divide it into three families. 



FAMILY I. 

 CICADARI^E. 



THIS family comprises those which have triarticulated tarsi, and usually 

 very small, conical, or fusiform antennae, composed of from three to six 

 joints, the extremely attenuated seta which terminates them included. The 

 females are provided with a serrated ovipositor. 



Some Singers have antennae composed of six joints, and three ocelli. 



CICADA, Olivier. TETTIGONIA, Fabricius. 



These insects (the Locusts), of which the elytra are almost always trans- 

 parent and veined, differ from the following ones, not only in the composition 

 of their antennae, and the number of the ocelli, but in the absence of the 

 faculty of leaping and in the music of the males ; which, in heat of summer, 

 the epoch of their appearance, produce that loud and monotonous sound which 

 has induced authors to designate them by the name of Cantatrices or 

 Singers. 



The organs by which it is effected are situated on each side of the base of 

 the abdomen: they are internal, and each one is covered by a cartilaginous 

 plate, which closes like a shutter. The cavity which encloses this apparatus 

 is divided into two cells by a squamous and triangular septum. When viewed 

 from the side of the abdomen, each cell presents anteriorly a white and plaited 

 membrane, and lower down, in the bottom, a tight, thin, transparent mem- 

 brane, which Reaumur terms " le miroir." If this part of the body be 

 opened above, another plaited membrane is seen on each side, which is moved 

 by an extremely powerful muscle composed of numerous, straight, and parallel 

 fibres, and arising from the squamous septum. This membrane is the tymbal. 

 The muscles, by rapidly contracting and relaxing, act on the tymbals, alter- 

 nately tightening and restoring them to their original state. Such is the 

 origin of these sounds, which can even" be produced after the death of the 

 insect, by jerking the muscle. 



The Cicadye live on trees or shrubs, of which they suck the juices. The 

 female, by means of an ovipositor enclosed in a bilaminated, semitubular 

 sheath, and composed of three narrow, elongated, squamous pieces, two of 

 which terminate in the form of a file, pierces the dead twigs to the medulla, 



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