COLEOPTERA : STRUCTURE. 



339 



anatomy, that the Coleoptera are the most perfectly organized 

 of insects, and consequently as being entitled to the highest 

 rank. 



The body consists of the head; a large segment, which 

 has been generally termed the thorax; two short incon- 

 spicuous segments, which support the wing-covers and 

 wings, and the two posterior pairs of legs, and which are 

 the meso- and metathorax ; and lastly, a continuous series 

 of rings which compose the abdomen, and which are not 

 furnished with locomotive organs. The head is generally 

 of a rounded form, furnished with a pair of antennae, ex- 

 tremely varied in their form in the different famihes, but 

 which, in the majority, consist of only eleven articulations : 

 they often differ in the sexes, those of the males being 

 larger, longer, or laterally more developed than in the other 

 sex. The eyes, which are always composite and facetted, 

 are generally lai-ger and globular in the carnivorous species, 

 as well as in those which, from the slowTiess of their habits, 

 have great need of defence against their enemies. Some 

 few species have been asserted to possess ocelli. The mouth 

 consists, as in all masticating insects, of an upper lip 

 (labrum, a), a pair of horny upper jaws moving horizontally 

 (mandibles, b b), two lower jaws (maxillae, cc) of a less firm 



consistence, but more complex in their organization, bearing 

 a palpus {d) or feeler, and furnished moreover with a lateral 



