562 



INSECTA. 



yellow, spotted with black, and which Shaw and Denon have figured in the accounts of their voyages in Africa ; 

 they then reduce them to powder, which they use as flour, as 1 learn from M. Savigny. These two species, and 

 some others, have a conical prominence upon the presternum, and compose the genus Acrydium. Amongst 

 those which do not present this character, and in which the antenn;e are equally filiform, some have the 

 wing-covers and wings perfect in the two sexes, and belong to the genus which I have named (Edipoda. In this 

 number are O. stridulus, G. Cicrulescens, [G.flavipes, and a great number of smaller species found in this country, 

 usually called Grasshoppers, but distinguished by their shorter antenna;.] 



Other Acrydia, similarly winged and with filifonn antenna?, have the upper part 

 of the prothorax strongly elevated, very compressed, forming a sharp crest, rounded 

 and prolonged into a point behind. Foreign countries possess numerous species, 

 one only of which, and of smaller size, is found in the south of France {A^ arma- 

 tum, Fischer.] 



In the others, one of the sexes, at least, has the wing-covers and wings very short, 

 and in nowise fitted for flight. I have formed for these a new generic group, named 

 Podisma. 



The Acrydia which have the antenna; thickened at the tips, either in both sexes or in only one of them, are 

 formed also into a peculiar genus, Gomphoccrus, by Thunberg. G. sibiricus, and other small British species. 



In the second division of the genus Acrydium, the prosternum receives in a cavity a part of the under-side of 

 the head ; the tonguelet is quadrifid, and the tarsi have no pulvillus between the ungues ; the antenna; have only 

 13 or 14 joints ; the thorax is prolonged behind like a large scutellum, which is sometimes longer than the entire 

 body, and the wing-covers are very small. These Orthoptera form the genus 



Tetri.v, Latr. (Acrydium, Fab., part of Gryllus bulla, Linn.), which is composed of very small species. 



Fig. 93.— G. fla 



THE SEVENTH ORDER OF INSECT&,— 



THE HEMIPTERA (Rhynoota, Fabr.),— 



Terminate in our system the numerous division of insects furnished with wing-covers, and 

 being the only ones among them which have neither mandibles nor maxilla;, properly so 

 called, [that is, fitted for biting]. A tubular articulated tongue, cylindrical or conical in its 

 form, curved downwards, or directed under the breast, having the appearance of a kind of 

 rostrum ; presenting throughout its whole upper face, when stretched forward, a gutter, or 

 canal, out of which three scaly, stiff, slender, and pointed setse may be withdrawn, and which 

 are covered at the base by a tonguelet ; these seta; form unitedly a sucker, resembling a sting, 

 having for its sheath the tubidar piece above described, and in which it is kept by means of 

 the superior tonguelet [or labrum], situated at its base. The inferior seta is composed of t(vo 

 threads united into one at a short distance from their origin ; thus the number of the p'eccs 

 of the sucker is, in reality, four. M. Savigny considered that the two superior setae, or those 

 which are separate, represent the mandibles of the biting insects, and that the two thi eads of 

 the inferior seta answer to the maxillae (or rather, as it appears to me, to their terminal lobes, 



which in the Bees and Butterflies are transformed 



,!?^ 



w 



into an elongated filament) ; hence the lower lip 

 is replaced by the tubular sheath of the sucker, and 

 \'i'^_.tf' the triangular piece at the base becomes the labrum. 

 The tonguelet, properly so called, also exists, and 

 under a form analogous to that of the preceding 

 piece, but bifid at the tip (see Cicada) ; the palpi 

 are the only organs which have entirely disappeared, 

 and vestiges of them are perceived in Thrips, [which, 

 however, are now proved to belong to an order dis- 

 tinct from the present ; palpi, small and inarticulate, 

 also exist in some of the Hydrocorisae]. 



The mouth of the Hemiptera is, therefore, fitted 

 only for extracting by suction fluid matters : the 

 deUcate threads of which the sucker is formed pierce the vessels of plants and animals, and the 



Fig. 94. — Promuscis 

 o, ucelli ; a, base c 

 lip, or canal ; »i, m; 



>f Hemiptera. Pentatnnia. 

 antenn.'e ; 1 1, upper lip ; 

 Itlibular, and mj', maxillary ! 



/i? 



