430 CLASS VT1T. 



The disagreeable smell, peculiar to most heteroptera, seems for their 

 protection, and is caused by a fluid that escapes through two aper- 

 tures, one on each side, beneath the thorax at the insertion of tlio 

 third pair of feet. According to LEON DUFOUR this fluid is 

 secreted by a small round or oval pouch, commonly of a yellow 

 colour, which is situated in the abdomen; it is rarely double. 



Many genera of hemiptera are met with only in warm countries, 

 and the European species form but a small part of the numerous 

 order. 



Section I. Homoptera. Elytra deflected, in most coriaceous or 

 membranous, similar to posterior wings, but larger and stronger. 

 Rostrum rising from the inferior part of head, inflected beneath the 

 breast between the bases of the feet. Thorax gibbous, with first 

 segment shorter. 



In this division, which as well as the second, WESTWOOD ranks as 

 a distinct order, the upper wings are constantly of a similar substance, 

 and not half-horny or leathery and half- membranous. The antennae 

 consist in many of more than six joints. The beak lies on the 

 breast (rostrum pectorale). All live on juice of plants. The females 

 often have an instrument for laying their eggs, composed of three 

 filaments, toothed plates or saws, enclosed between two valves. 



A. Metamorphosis (in males at least) complete. 



Family XXXV. Coccina ( Gallinsecta REAUM.) Males winged, 

 with mostly two wings, without rostrum. Wings without cells, 

 with only two longitudinal nervures. Antennae mostly with nine 

 to eleven joints. 



Females (one genus excepted) apterous, attaching themselves to 

 trees or herbs at the time of parturition, sometimes assuming the 

 form of a gall, their own vesicular dead bodies covering their eggs. 



Gall-insects. These insects were thus named by REAUMUR from a 

 superficial resemblance of the pregnant female to a gall-nut. (See 

 above, p. 384). The joints of the tarsus have not been given by 

 us amongst the characters on account of the minuteness of the 

 objects and the prevalent uncertainty; for whilst many writers (ex. 

 yr. LATREILLE and WESTWOOD) ascribe one joint alone to this family, 

 and distinguish it principally by this, others assign three (BoucHE 



