314* NATURAL ARRANGEMENT OF INSECTS. 



extending considerably beyond the abdomen : their an- 

 tennae are dilated into an abrupt, compressed, three- 

 jointed clava ; and in some the inside of the anterior 

 tibia of the male has, towards its apex, a long decumbent 

 spine. Other cognate genera have not the sides of the 

 elytra enlarged. 



(279-) Our next sub-family, the Chrysomelidce, are 

 convex insects, generally ovate: they differ from our 

 second section of the preceding, in having four obvious 

 joints to the tarsi; antennae not clavate; and their 

 larvae, at least those of the type, are naked, and feed 

 upon the leaves of plants, leaving nothing but the 

 fibrous skeleton. The Galerucidce, which contain also 

 Halticdy but we think very incorrectly, considering the 

 different structure and habits both of larva and imago, 

 are a component portion of the present family: the 

 latter are remarkable for the great enlargement of their 

 posterior legs, which gives them the power of leaping ; 

 and they are the only insects, throughout the phyto- 

 phagous division of the Coleoptera, that possess this 

 power. Their larvae and themselves are exceedingly 

 destructive to plants ; and our farmers have frequent 

 occasion to execrate their existence, on account of their 

 spoliation of turnip crops, one of these little skipping 

 insects being the well-known and formidable turnip 

 fly ; their larvae feed between the membrane of leaves, 

 upon the parenchyma. Tritoma and Triplax, which 

 British entomologists have usually associated with the 

 Engidce, evidently come into this group somewhere ad- 

 jacent to Chrysomela : they are fungi vorous insects; 

 and some of the exotic species are very conspicuous for 

 size. The types of the sub-family Galeruca are formed 

 like the preceding, but they do not jump, and occur 

 chiefly in humid situations. 



(280.) Our next family, the Clythrida, are all 

 insects of a heavy obtuse form ; sometimes, as in 

 Chlamys, of a rough and very unequal surface, more 

 resembling a cluster of irregular crystals than an insect : 

 it is exclusively American. Clythra itself is more 



