HOMOPTERA. 415 
The insects composing this order comprise some of the most ano- 
malous forms to be met with in this class of animals. The musical 
Cicade, the strangely formed lanthorn flies, the cuckoo-spit insects, the 
destructive aphides, and the extraordinary scale-insects, are all types 
of well-marked groups in the order, agreeing together in the more 
or less membranous nature of their four wings, their promuscidate 
mouth, and their transformations. The body is generally thick and 
convex, rather than depressed ; the wings consequently assume a de- 
flexed position in repose ; the promuscis arises much nearer to the 
breast than in the Heteroptera, having sometimes the appearance of 
being pectoral; the antennz often arise from the under surface of 
the head, being mostly short, the basal joint very thick, and the 
terminal ones very slender and setigerous ; the segments of the thorax 
form a solid thick ovate mass, the anterior being generally shorter 
than the following; the tarsi are always very short, and never have 
more than three joints. All the insects of this group subsist upon 
vegetable juices, which they obtain by the assistance of their pro- 
muscis. Sometimes, as in the case of the Aphides, Cocci, and sugar= 
cane fly (Delphax saccharivora), the injuries which they thus commit 
upon plants is very considerable. In some species, the promuscis is 
almost as long as the body, the labium itself being of that length, as 
in the Fulgore ; but in others it is extremely short, the four internal 
setae not much exceeding the labium in length ; in the Coccida, how- 
ever, these sete are exceedingly long, but retractile, the sheath itself 
being very minute. The females are often furnished with a scaly 
ovipositor, composed of several toothed saws, lodged, when at rest, 
in a bivalve sheath at the extremity of the under side of the abdomen ; 
being enabled, with this apparatus, to make an incision in the leaves 
oer stems of plants, into which they afterwards introduce their eggs. 

Say, in Journal of Acad. Nat. Science. Philadelph. vol. vi. p. 2, 
Serville and St. Fargeau, in Encyclop. Méthod. tom. x. 
Dufour. Recherches Anatomiques et Physiol. sur les Hémiptéres. Paris, 1833. 
4to. (Extr. from Mém. des Say. E’trangers, tom. iv.) 
Burmeister. Handbuch der Entomol. zweit. band, 1835. — Ditto, Genera Insecto- 
rum icon illust. No. 1—4. Berlin, 1838, 
Guérin, in Voyage de la Coquille. — Ditto, in Voyage Duperrey et Belanger. 
And the general works of Linneus, De Geer, Palisot Beauvois, Coquebert, Perty 
(Del. An. Art. Brazil.), Zetterstedt, Curtis, ec. 
