216 



MODERN CLASSIFICATION OF INSECTS. 



dilated hind legs, the dilatation of the anterior tarsi, or the bearded 

 nientum in the various groups. 



The habits of the New Holland species of these insects have not 

 been recorded, but the molary structure of the internal base of the 

 mandibles and the obtusely toothed maxillae seem to prove them to 

 be pre-eminently phyllophagous. The Brazilian species of Geniates 

 fly round the trees in the evening, remaining amongst the leaves or in 

 crevices in the bark during the day, and feeding upon the plants. 

 The Leucothyrei, on the contrary, are not found amongst the leaves, 

 but burrow into the soft trunks of trees, which they reduce to a soft 

 paste (Perty.) 



Mr. MacLeay considers that the larvas of the typical genus are the 

 New Holland grubs, said to be as useful to the natives as articles of 

 food, as they are injurious to the agricultural hopes of the European 

 settlers. 



The species are numerous in New Holland and South America^ 

 where they appear to take the place occupied in the Old World by the 

 Melolonthidse : they do not appear to extend farther than 45° from 

 the equator. 



The eighth family MELOLONTiiiDiE is a very extensive and widely 

 distributed group, distinguished by having the labrum transversely 

 divided, generally into two lobes, the centre being more or less strongly 



Fig. 22. 



emarginate {Jig.22.-2. underside of head, and 22. 3. labrum of the com- 

 mon Cockchafer, Melol. vulgaris) ; the mandibles {Jig. 22. 4.) are robust, 

 horny, often obtuse at the point, but with the internal margin acute at 

 the apex, thus serving to cut the leaves upon which the insects feed, 



