102 THE INSECT WORLD. 



white, and of elongated shape, which it deposits on the stems and 

 leaves of aquatic plants. The eggs are hatched at the beginning 

 of spring, or in May, and the young ones at once begin to swim 

 about like their mother, on their backs, belly upwards. M. Leon 

 Dufour says on this subject : 



" A dorsal region, raised like a donkey's back, or like the rounded 

 keel of a boat, and covered with a velvety substance, which renders 

 it impermeable, numerous fine fringes which garnish either the 

 hind legs, or the borders of the abdomen and thorax, or lastly in 

 a double row a small crest or comb running down the surface of 

 the belly, and which spread themselves out or fold themselves 

 in at the will of the insect, just like fins, favour both this supine 

 attitude and the accuracy of the swimming movements of the 

 Notonecta. Since nature, which seems often to delight in pro- 

 ducing extraordinary exceptions to her ordinary rules, thus bearing 

 witness to the immensity of her resources, had condemned this 

 animal to pass its life in an inverted position, it was necessary, for 

 the maintenance of its existence, that it should provide it with an 

 organization in harmony with this attitude. It is also for this 

 object that its head is bent over its chest ; that its eyes, of an oval 

 shape, can see below from above ; that the front as well as the 

 middle legs, agile and curved, solely destined for prehension, can 

 to a certain extent become unbent by means of the elongated 

 haunches which fix them to the body, and clutch firm hold of 

 their prey with the strong claws which terminate the tarsi." 



HOMOPTERA. 



We come now to the second group of order Hemiptera, namely 

 Homoptera. 



The insects which compose this division are numerous. They 

 may be arranged into three great families, of the most remarkable 

 members of which we shall give some account. These are the 

 Cicadarite, the Apkidii or Plant-lice, and the Gallinsecta. 



The Cicada is the type of the first of these families. It has a 

 deafening and monotonous song ; as Bilboquet says, in the " Saltim- 

 banques," " those who like that note have enough of it for their 

 money." Yirgil pronounced a just criticism on the song of the 



