116 COLEOPTERA. 



ORDER COLEOPTERA. 



The Coleopterous insects are characterized by having 

 four wings, of which the anterior pair, always hard or 

 leathery in their texture, form two strong shields, 

 beneath which the hinder pair are lodged and pro- 

 tected. The front wings, or elytra* when in repose 

 are always united by a straight edge, extending along 

 their whole length. The hinder wings, which alone 

 are adapted for flight, are much larger than the 

 elytra, and when not in use, are folded transversely ; 

 in a few species they are wanting, and then the 

 elytra are, as it were, soldered together. The tegu- 

 mentary envelope of these insects is always remark- 

 ably hard, and forms a very substantial suit of 

 armour ; their mouth is constructed for the mastica- 

 tion of food, and is provided with a pair of strong 

 mandibles, a pair of maxillae bearing palpi, and a 

 labium or lower lip, also bearing palpi. The abdomen 

 is sessile, that is, is broadest at the place where it 

 joins the thorax, 



The metamorphosis which the Coleoptera undergo 

 is complete. The larva resembles a worm ; its body 

 is soft, with the exception of the head, and the first 

 segments of the body, which are of a horny consist- 

 ence. They are generally furnished with three pairs 

 of horny legs, attached to the three first rings, but 

 sometimes these are replaced by fleshy tubercles. 

 There is, however, never a greater number than six 

 of these appendages. The pupa is motionless and 

 takes no food, its limbs being swathed together by 

 the external integument. It is generally enclosed in 

 a shell or cocoon, composed of different substances, 

 joined together by a viscid silky material ; sometimes 

 it is naked. This is by far the most numerous of all 

 the insect orders ; the number of species already 

 known is probably not much less than fifty thousand. 

 In order, therefore, more readily to arrange such a 



* tKvrpov, elytron, a case. 



