INSECTS 



353 



like in appearance. The males are provided with musical organs 

 on the under-side of the thorax, by which they are enabled to 

 make a chirping sound, the well-known "song of the Cicada". 

 The eggs are deposited in the branches of trees by means of a 

 piercing organ with which the tail of the female is provided, and 

 from them are hatched wingless larvae, which dig into the ground 

 by means of their fore-legs and subsist on the juices of roots, 

 ultimately making their way up again and becoming adult. The 

 larvae may remain as such for a long period, in one North 

 American species for seventeen years. Cicadas, of which there 

 are very numerous species, inhabit the warmer parts of the earth, 

 some of them being natives of South Europe. 



Lantern-Flies and their allies make up a closely-related family, 

 many members of which are beautifully coloured, but the species 

 found in Europe (including Britain) are not highly endowed in 

 this respect. The name "lantern-fly" has not been so far justified. 



Most persons have seen, during the summer months, those 

 frothy masses on plants to which the name "cuckoo spit" is 

 vulgarly given. These en- 

 close the larvae of small insects 

 belonging to this sub-order, 

 and known as Frog-Hoppers 

 on account of their leaping 

 powers. 



Plant- Lice, or Green-Flies, 

 furnish other examples (fig. 

 205). The best-known forms 

 are the little green aphides 

 common on geraniums and 

 other garden plants, and which, like their immediate allies, are 

 distinguished by a complex life-history. The Vine - Louse {Phyl- 

 loxera vastatrix) is a creature of the kind which does immense 

 damage in vineyards. 



The Cochineal Insect (Coccus cacti), on the other hand, is of 

 economic importance. It is a native of Mexico and Central 

 America, where it feeds upon cacti. 



2. Heteroptera. — To the insects of this sub-order the name 

 "bug" is properly applied. When wings are present, the front 

 pair are transformed into wing-covers, the tips of which, however, 

 remain membranous. Many of the species are distinguished by 



Fig. 205. — Cabbage Aphis '\Aphis brassica) 



1. 2, Male (natural size and enlarged); 3, 4, female (natural 

 size and enlarged) 



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