ARTICULATA. 



143 



Southern Atlantic and the intertropical regions of the Pacific. Most of the 

 s^Decies have been described from wingless individuals, probably larvi^. 



Orders of Insects. 



The distribution of insects into orders has been one of the chief problems 

 of Entomology, and one about which there is a great want of unanimity. 

 Latreille, the father of modern Entomology, who was born in 1762, and 

 devoted a long life to the science, proposed a system in 1796, which he 

 subsequently modified in various editions of his works, in 1806, 1817, 1825, 

 1829, and 1832. In these he adopted the following arrangement of the 

 orders, which is still very generally followed : 



A. Insects without wings. 

 a. "Without metamorphosis, 



* Mouth mandibulate, 

 ir% " suctorial (lice), 



h. A metamorphosis (fleas), . 



B. Insects with wrings. 

 a. Elytroptera, 



(Anterior wing acting as a sheath for the poster 



* Mouth mandibulate, 

 AVing-covers horny, metam. perfect, . 



" " " ' " imperfect, 



" " coriaceous, " " . . 



*-^ Mouth suctorial, " " . . 



h. Gymnoptera (wings alike), 



* Wings four. 



f Mandibulate, mandibles distinct. 

 Wings reticulated, .... 

 " veined, ..... 

 ff Mouth suctorial, mandibles abortive, . 

 ** AVings two. 



f Two twisted halteres before the wings, 

 f f Halteres two, behind the wings, . 



1. Thysanuka. 



2. Parasffa. 



3. SiPnoNArxERA. 



ior one.) 



4. coleoptera. 



5. Dermaptera. 



6. Orthoptera. 



7. Hemiptera. 



8. Neuroptera. 



9. Hymenoptera. 



10. Lepidoptera. 



11. pHIPIPTERii. 



12. DiPTERA. 



It must be borne in mind that the same name is in some cases not given 

 to the same group by different authors, and that the same order sometimes 

 has several names. The English authors exhibit a fondness for numerous 

 orders, separating, for example, the CicadiB from the Hemiptera, under the 

 name of Ilomoptera. 



After various modifications, Burmeister proposed, in 1839, a very different 

 arrangement, founded principally upon the metamorphosis, of which he 

 admits two grades, one half, the other entire, according to w^hich he names 

 insects Hemiinetabola {Ametahola of Leach) and Tlolometabola {Metahola 

 of Leach), each of which contains haustellate and mandibulate orders, of 



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