BUGS. 213 



destitute of wings, except in one sex of the lowest group ; but some have these organs 

 short and unfinished, and it is but very rarely that we meet with one of this kind 

 fully winged. A striking instance of this nature occurs in the genus Phylloscelis, 

 which has been based upon characters derived only from the uncompleted insects. In 

 the chief forms of this sub-order the wings and hemelytra are large, slant downwards 

 like the roof of a house, are of nearly equal texture throughout, although sometimes 

 thin and transparent, and are numerously and continuously veined. A few notable 

 exceptions to the decumbent position of these organs occur in such genera as 

 Flatoides, Dascalia, and Helicoptera ; while in Poeciloptera and Ormenis they are 

 held nearly vertical. 



This division is also remarkable for the blunt face, and backward-pressed elements 

 of the head and breast, thus carrying the rostrum far underneath. These modifica- 

 tions are seen carried pretty far in Cicadas and Membracidae ; although much dis- 

 guised by the inflated or prolonged frontal protuberances in Laternaria, Fulgora, 

 and Nersia. 



Both kinds of eyes are generally present in this group ; the compound ones being 

 commonly large and prominent, while the simple ones, ocelli, are like little convex 

 gems, placed between the larger eyes on the vertex or front ; but occasionally, as in 

 Fulgoridae, on the sides of the cheeks, between the latter and the antennae. There 

 are usually two ocelli, although in Cicadidaa and most Psyllidaa they are three in 

 number, and are placed in front, forming a triangle. 



The antennas are usually situated in a hollow below the eyes, and are composed of 

 a few expanded joints at the base, with a tapering, slender bristle-shaped termination. 

 (Exceptions occur in Psyllidae, Aphididse, and Coccidae, where these organs are 

 commonly filiform, and somewhat thickened at tip.) There are two principal types 

 of legs in this division, although these are variously modified for particular modes of 

 life : the one adapted for crawling, the other for leaping. The former have short legs, 

 generally stout, as in the Cicadas and some of the Fulgoridae ; the latter have the hind 

 legs long, often curved and set with rows of stiff spines, such as we see in Jassus, 

 Tettigonia, etc. 



SUPER-FAMILY STEKNORHYNCHI. 



A very comprehensive alliance of usually very small and feeble insects presents 

 itself at the outset of the sub-order, and forms an upwardly gradative combination 

 leading to the truly representative Homoptera. It embraces the four families, 

 Coccidae, Aleyrodidae, Aphididae, and Psyllidae, or the creatures generally known by 

 the names scale lice, mealy bugs, bark lice, plant lice, and the Psyllas, or jumping 

 lice. Their boundless fecundity and capacity for distribution fit them for the wide- 

 spread injuries which they occasion in fruit-growing regions throughout the globe. 



The name Sternorhynchi has reference to the rostrum, which apparently arises 

 from the sternum between the anterior feet, and is the most characteristic element of 

 structure which pervades the group. Divested of external disguises, the body of 

 these insects is generally conical, either compressed, flattened, or pear-shaped; with 

 filiform rather than bristle-shaped antennae composed of numerous joints. 



Claus has erected these four families into a siib-order, and employed the name 

 Phytophthires as a designation, but as this term was devised by Burmeister for a 

 group including only the Aphidae and Psyllidae, we decline to wrest it from its original 

 signification, and hence adopt that of Amyot and Serville instead. 



