HEMIPTERA. 171 



NoTONECTA, Geoff., Fab. 



Where the scutellum is very distinct, the rostrum forms an arti- 

 culated and elona^ated cone, the wings are tectiform, and all the tarsi 

 biarticukted. The four posterior legs are geniculate, and have sim- 

 ple, cylindrical tarsi, terminated by two hooks. 



N. glauca, L., Roes., lb., XXVII. Six lines in length ; yel- 

 lowish above, -with a russet tint on the elytra, the inner margin 

 of which is spotted Avith blackish ; scutellum black. 



To seize its prey with more facility it swims on its back ; it 

 stings severely *. 



The second section of the Hemiptera, that of theHojiopxERA, Lit.. 

 is distinguished from the preceding one by the following charaj 

 the rostrum arises from the lowest portion of the head, near thj 

 tus, or even from the interval between the two anterior leg^ 

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

 out and semimembranous, sometimes almost similar to the 

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

 frequently shorter than the second. 



All the Insects of this section feed exclusively on vegetable y 

 The females are provided with a scaly ovipositor f, 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. 



CICADARLE. 



This family comprises those Avhich have triarticulated tarsi, and 

 usually very small, conical, or fusiform antennae, composed of from 

 three to six joints, the extiemely attenuated seta Avhich terminates 



* Fab., Syst. Ryngot. ; Lat., Gener. Crust, et Insect., Ill, p. 150. The genus 

 Plea, Leach, which that gentleman establishes on the Notonecfa mianfissima of Lin- 

 naeus, and which must not be confounded with the one so styled by Fabricius and 

 other entomologists, differs from Notonecta, inasmuch as the third joint of the an- 

 tennae is larger than the others, and because those of the anterior tarsi are almost 

 of the same length, and the hooks of the posterior ones are large. The body is 

 shorter, and the elytra entirely crustaceous, arched, and truncated at the exterior 

 angle of their base. A piece is observed there, analogous to that remarked in the 

 same place in the Cetoniae. 



t Called oviscapte by M. Marcel de Serres. 



n2 



