180 AN INTRODUCTION TO ENTOMOLOGY. 



several species of Leaf-hoppers that infest the leaves of grape, and 

 are known to grape growers as the " Thrip." These all belong to 

 the genus Erythroneura. The most common one is E. vltis. It is 

 a little more than 3 mm. (0.12 inch) in length, crossed by two blood- 

 red bands, and a third dusky one at the apex. These insects pass 

 the winter in the perfect state, hibernating under dead leaves or 

 other rubbish; in the spring they deposit their eggs on the young 

 leaves of the vine. The larvae hatch during the month of June, and 

 resemble the adult insect except in size and in being destitute of 

 wings. The insects feed together on the under side of the leaves, 

 and are very quick in their movements. Like the preceding species 

 this insect can be destroyed by trap-lanterns or by washes. 



The Rose Leaf-hopper, Empoa rosce. " Swarms of these insects 

 may be found, in various stages of growth, on the leaves of the rose- 

 bush, through the greater part of the summer, and even in winter 

 upon housed plants. Their numerous cast skins may be seen adher- 

 ing to the lower sides of the leaves. They pair and lay their eggs 

 about the middle of June, and they probably live through'the winter 

 in the perfect state, concealed under fallen leaves and rubbish on the 

 surface of the ground." Although this is a very common pest, it 

 does not seem to have received much attention from entomologists 

 since the time of Harris, from whom the above account is quoted. 

 It should be combated in the same way as the leaf-hoppers already 

 described. 



Sub-family II. TETTIGONIN^:.* 



The members of this sub-family are mostly small or medium-sized 

 insects, with long narrow bodies. But we find here some forms 

 which resemble certain genera belonging to the Cercopidae. Thus 

 Penthimia includes plump, short-bodied insects, which remind us of 

 Clastoptera; and the genus Gypona includes a large number of species, 

 some of which resemble very closely certain species of Aphrophora. 

 It is, however, hardly necessary to remind the student that a glance 

 at the posterior tibiae of these leaf-hoppers will enable one to dis- 

 tinguish them from the Cercopids, which they so closely resemble. 



The genus Diedrocephala includes grass-green, or pale-green, 

 spindle-shaped species which represent better the typical form of 

 this sub-family. The members of this genus may be recognized by 

 the long, triangular head as seen from above. One of the species, 



* Tettigonlnae, Tettigonia : tettix (rernt-), a cicada; gonia (ycovia), a corner. 



