Hemiptera 195 



hind pair, and are frequently coloured while the latter are trans- 

 parent. The family is generally distributed. 



Cercopids. — The Ctfrco^iaie are distinguished from the Fulgoridas 

 by the insertion of the feelers between, not beneath the eyes. 

 There are two ocelli. The pronotum has an angular notch on 

 the hind margin, and the scutellum is accordingly rhomboidal. 

 The forewings are decidedly firm in texture, often clothed with 

 fine, short hairs ; the hind shins are cylindrical, each with 3. 

 terminal row of spines, and with two spines on the outer side. The 

 nymphs of our native species of this family (which is generally 

 distributed) live on plants where they protect themselves by a 

 frothy secretion — the well-known " cuckoo-spit." 



Membracidae. — The MembradcLe are characterised by the crown 

 of the head being vertical (bearing two ocelli), so that the face 

 looks almost directly downwards. The pronotum is produced 

 behind into a long process. The hind-haunches are large and 

 the thighs of the legs are triangular in section. The family is 

 poorly represented in Europe (only two species inhabit the British 

 Isles), but in tropical countries the species are numerous and often 

 very remarkable in form on account of the striking development 

 of the pronotal processes. 



lassidae. — The lussida are a very large family of small insects, 

 together with the smaller species of the Cercopidse known as 

 " Frog-hoppers." They are distinguished from the CercopidjE 

 by the prismatic hind-shins and the triangular scutellum ; from 

 the Membracids by having no prosternal processes. The young 

 nymphs are soft-skinned and often protect themselves by " cuckoo- 

 spit." The family is of general distribution. 



The four remaining families are distinguished from the six 

 preceding by having only two tarsal segments, 



Psyllidae. — The PsylHiLe or "Jumpers" are a very large family 

 of small insects. The feelers are long, with ten segments, the 

 first two segments short and stout, the remainder finely thread- 

 like, the terminal segment with two divergent bristles. The 

 head is broad with prominent compound eyes and three ocelli. 

 The legs are short with thick thighs, and the forewings are 

 usually firm in texture. The family is widely distributed, and 

 the species are very numerous on plants (l2l). 



Aphidae. — The AphiiLe or Plant-uce are a very large family of 

 soft-skinned insects with feelers of five to seven segments, usually 

 longer than the body, no ocelli, long slender legs, and delicate 

 hyaline wings with few nervures. Often, however, the mature forms 

 are wingless. A pair of tubes on the hind-body are usually present, 

 through which a " honey-dew " secretion is discharged (fig. 109). 

 The young aphids are closely like their parents ; in most species 

 active young are produced in great numbers through the summer 



