430 INSECTA. 



swim or row with great swiftness, and frequently while on their back. 

 They compose the genus 



NoTONECTA, Lin. 

 Which has been divided into Corixa and Notonecta proper. 



The second section of the Hemiptera, that of the Homoptera, 

 Lat., is distinguished from the preceding one by the following char- 

 acters: the rostrum arises from the lowest portion of the head, near 

 the pectus, or even from the interval between the two anterior legs: 

 the elytra — almost always tectiform — are of the same consistence 

 throughout and semimembranous, sometimes almost similar to the 

 wings. The three segments of the trunk are united en masse, and 

 the first is frequently shorter than the second. 



All the Insects of this section feed exclusively on vegetable juices. 

 The females are provided with a scaly ovipositor, usually composed 

 of three dentated 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^. 



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 ovi- 

 positor. 



Some — Singers — have antennas composed of six joints, and three 

 ocelli. 



Cicada, Oliv. — Tettigonia^ Fab. 

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

 parent and veined, differ from the following' ones, not only in the composi- 

 tion of their antennx 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 



