114 NATURAL HISTORY. 



America, where they occur in wonderful abundance and variety. Our figures (E, F, G, H, I, in Plate 63} 

 will show some of the curious forms that they assume. Some of the most remarkable are the species 



of Bocydium black insects, with transparent wings, the prothorax 

 of which bears a perpendicular process, terminating in a knob, 

 from the sides of which issue two branches, also branched and 

 knobbed, whilst from behind is given off a long slender process, 

 extending about as far as the extremity of the closed wings. 

 Several species occur in South America, and from the sleiideriiess 

 of these singular thoracic processes, some of them are very elegant 

 little creatures. 



The extra-American species of this group belong chiefly to the 

 genus Centrotuv, one species of which (C. cornutus) is common in 



BOCYDIUM TINTINNABULIFERUM. Britain and Europe. It is rather over a quarter of an inch long, 



black, with a pair of upright horns on the prothorax, which is also 



produced behind into a long, pointed, keeled spine. Another common European and British 

 species (Gargara genista;) is smaller than the preceding, and has no horns on the prothorax. 



FAMILY XVI. CICADELLINA. 



We apply this term to a very extensive group of Homoptera, of small or moderate size, which in 

 many respects may be regarded as the analogues of the Phytocoridae among the Bugs. In these 

 insects we find the prothorax of ordinary form and proportions, without any of those enlargements or 

 processes which characterise the preceding family, and the head, instead of being pressed downwards, 

 projects freely in front of the thorax, with the crown directed upwards and the forehead forwards, the 

 two surfaces usually meeting under a distinct angle. There are usually two ocelli ; the antennae are 

 short, and composed of two joints with a terminal bristle ; the upper wings are leathery ; and the hind 

 legs elongated and converted into leaping organs. These insects are distributed over all parts of the 

 world, and, with the exception of the Aphides, they constitute the most numerously represented group 

 of Homoptera in Europe and Britain. They live in all stages upon trees, shrubs, and plants, on the 

 juices of which they feed, and the larvae and pupae very commonly surround themselves with a 

 dense frothy secretion, whence the common name of " Cuckoo-spits " has been applied to them. 



Two groups of these insects may be distinguished, and these are usually easily recognised by the 

 form of the hinder limbs. In the CERCOPID^ these organs are smooth, or furnished only with two or 

 three spines arranged one behind the other on their hinder smiace, and the posterior coxae are short. 

 This group includes the largest species, some of the exotic species attaining a length of about an inch. 

 A Javanese species approaching this length (Cercopis bivittata) is shown on our Plate 63, c. It is 

 shining black, with two white bands across the fore wings. Black and red are more common colours 

 in the genus Cercopis, one species of which, so adorned (C. sanguijiolenta), is common on the 

 continent, and occurs in Britain. The most abundant European species of this group, however, are 

 the AjiJirophorce, which are the best known of the Cuckoo-spits, or Froghoppers. Aphropkora 

 spumaria, an insect nearly half an inch long, is common in Britain on trees and bushes, especially 

 willows ; a smaller species (-4. bifasciata) is found abundantly upon rose-bushes and other plants in 

 every garden. 



The JASSID^E have the hinder coxae transverse, and the hind tibiae furnished with two rows 

 of more or less distinct spines along their posterior surface. They are exceedingly numerous, 

 and often remarkably elegant in form. The species of Tettigonioe (T. quadripunctata, Plate 63, D) 

 especially are frequently of great beauty. They are mostly inhabitants of America, whence some 

 three or four hundred species have been described, but we find in England an exceedingly pretty green 

 species (T. vlridis), which is common in damp meadows. The species of Typhlocybci, which are 

 exceedingly abundant on plants everywhere, resemble the Tettigonice in general form, biit are more 

 slender, and generally very small and delicate creatures. They have no ocelli. 



FAMILY XVII.-PSYLLID^]. 



This is the first family of the so-called Plant Lice, and is distinguished by having long, freely-pro- 

 jecting antennae of eight or ten joints, with a pair of fine bristles at the extremity of the last joint, 



