CLASS V. INSECTA, 137 



Cohors I. Odontata. 

 Mouth with mandibles, maxillae, and lip. Wings four. 



Order IV. — Neuroptera. V. IIymenoptera. 



Cohors II. SiPIIONOSTOMA. 



Mouth tubular, formed for sucking. 

 Order VI. Lepidovtera. VII. Diptera. VIII. Suctoriv. 



Latreille has retained the same general arrangement in his last work, 

 Cinsida-ations Ginirales sur I'Ordre Xatu?-elle, <^c. but he has rejected the 

 divisions into Legions, Centuries, and Cohorts. 



JJnmtrW, m hi^ Zoologic Aiiali/fi(jiie, arranges insects into Eight Or- 

 ders, the last of which also comprehends the Classes Arachndida and 

 Mj/rkqioda. 



In 1812 Lamarck published a little work, entitled Extraitdu Cours de 

 fj Zoologie du Museum d'Uistoire Naturelle, in which he has continued the 

 general arrangement published by him in ir.Ol. 



In 1815, vol. i.\. of the Edinburgh Eiuyc/oiucdiu was published, in 

 which Dr. Leach gave the following arrangement of Insects into Or- 

 ders, and has added to them the PitrasUa and ThtjsanoHru^ which La- 

 treille placed with the Artidnididd. 



Subclass I. A:\IETAB0LIA. 

 Ofder I. Thysanura. II. Axoplvra. 



Subclass II. METABOLIA. 



Century I. ELYTilROPTEllA. 

 Insects with elytra. 



Cohors I. Odontostomata. 



Mouth with mandibles. 

 * Metamorphosis incomplete. 

 Order III. Coleoptera. 



** Mclamorphosis nearly coaictate. 

 Order IV. Strepsiptera, 



*** Metamorphosis semi-complete. 

 prder V. Dermaptera. VI. Orthoptera. VII. Dictyopteba. 



Cohors II. SiPlIONOSTOMATA. 



jVIouth with an articulated rostrum. 



