HEMIPTERA. 49 
have a very flat body, broad head, and the abdomen rounded poste- 
riorly: Their legs are terminated by a little membranous vesicle 
accompanied beneath with two hooks. Four wide and flat pieces, 
which are the sheaths of the elytra and wings, distinguish the nymph. 
Several in this state, as well as in the first, are covered with a white 
substance resembling cotton, arranged in flakes. Their feces form 
threads or masses, of a gummy and saccharine nature. 
» Some species, by wounding plants in order to suck their Juices, 
produce excrescences somewhat resembling gall-nuts, particularly 
on their leaves or buds. Of this number is the 
P. buaxi; Chermes buxi, L.; Reaum., Mem., Insect., II, xix, 
1,14. Green, with brown-yellowish wings. 
Other species are also found on the Alder, Fig tree, Nettle, 
&c.(1) 
A species which lives in the flowers of the rushes has been erect- 
ed into a genus by Latreille, under the name of Livia. The an- 
-tenne are much thicker inferiorly than at their extremity(2). 
The remaining Aphidii have but six or eight’ joints in the 
antenne ; the last is not terminated by two sete. 
Sometimes the elytra and wings are linear,+fringed with 
hairs, and extended horizontally on the body, which is almost 
cylindrical; the rostrum is very small or but little distinct. 
The tarsi are terminated by a vesicular joint without hooks. 
The antenne consist of eight graniform joints. Such are the 
Insects which form the genus 
Turips, Lin. 
They are extremely agile, and seem to leap rather than fly... When 
we irritate them beyond a certain point they turn up the posterior 
extremity of their body in the manner of the Staphylini. They live 
on flowers, plants, and under the bark of trees. The largest species 
scarcely exceed one line in length(3). 
(1) See Fab., Geoff, De Geer. . 
(2) Lat., Gen. Crust. et Insect., ILI, p. 170; Arh., Faun. Insect., VI, 21. 
(3) See Lat., Ibid., p. ead., and the authors already quoted. In the organization 
of the mouth, I haye detected characters which seem to distinguish it essentially 
from that of Insects of this order. M. Straus, who has studied it with admirable 
minuteness, thinks that Thrips belong to the order of the Orthoptera. 
Voit. 1V.—G 
