722 CLASS IV. INSECTA. 



Order 19. COLEOPTERA.* 



The anterior wings, called elytra, are hard, and when at rest they 

 cover in the functional hind-wings and come together closely 

 with a straight median juncture ; mouth-parts biting, with stout 

 mandibles ; second maxillae much fused to form an effective lower lip. 

 Metamorphosis complete ; larva grub -like ; pupa soft and exhibiting 

 the parts of the imago. 



The Coleoptera form a very large Order with some hundred and 

 fifty thousand described species. Almost any member of the Order 

 may easily be recognized by the straight suture which in the 

 great majority of cases lies between the hard, leathery elytra, 

 or fore-wings, when they are at rest. The hind-wings alone are 

 used for flight, and the group on the whole is less given to flying 

 than the other large Orders of Insects. The head bears an- 

 tennae, whose segments vary in number from one to thirteen, 

 and biting mouth-parts. 



The prothorax is usually mobile ; the pronotum, and the elytra 

 when at rest, effectively cover in the body ; a small triangular 

 area of the mesonotum, situate at the base of the elytra and termed 

 the scutellum, being frequently the only other part of the dorsal 

 surface visible ; in many cases, however, the elytra are short, 

 and leave some dorsal abdominal segments exposed. The 

 sterna are usually clearly defined, as are the episterna and 

 epimera. The bases of the hind-legs cover part of the 

 anterior abdominal segments, of which usually but five are dis- 

 tinguishable ventrally, though seven or eight appear dorsally. 

 One or more segments are tucked into a genital bursa at 

 the posterior end of the body. 



The elytra are very rarely absent and then only in the female 

 sex ; but the hind-wings are not unfrequently diminished to the 

 smallest proportions, and in these cases the right and left fore- 

 wings are frequently soldered together. The elytra are often 

 ornamented with ridges and depressions. The hind-wings 

 .alone are membranous ; they have but few cross-nervures. 



* Strauss-Durckheim, Monograph, Paris, 1828. Horn, Revision der 

 Cicindeliden, Berlin, 1898. Regimbart, Ann. Soc. Ent. France, 1882-3 

 and 1886. Raffray, Rev. Ent. franc., ix, 1890. Ganglbauer, Die Kdfer 

 von Mitteleuropa, Vienna, in progress. Ferris, Larves de Coleopteres, 1898. 

 Newport, Tr. Linn. Soc., xx, 1851. Lacordaire, Genera des Coleopteres 

 (Suites a Buffon), x, Paris, 1874. Mulsant, Coleopteres de France. 



