CLASS INSECTA, 7 



A few insects, and always without wings, such as the 

 myriapodes or millepedes^ approximate to many Crustacea 

 cither in the quantity of rings of the body and of their feet, 

 or in some traits of analogy in the conformation of the parts 

 of the mouth ; but all the others have constantly but six 

 feet ; and their body, the number of segments in Avhich 

 never exceeds a dozen, is always divided into three principal 

 portions, the head, the trunk, and the abdomen. Among 

 these last, some have no wings, and preserve during life the 

 form which they had when born, merely growing and changing 

 their skin.* In this respect they have some relation to the 

 animals of the preceding classes. The other insects with six 

 feet are almost all winged ; but the wings, and frequently 

 even the feet, do not appear at first, aiid are not developed 

 until after a series of changes, more or less remarkable, 

 called metamorphoses, and which we shall shortly describe. 



The headf is the seat of the antennae, the eyes, and the 

 mouth. The composition and form of the antennae vary 

 much more than in the Crustacea, and are often more deve- 

 loped in the males than in the females. 



The eyes are either complicated or smooth : the former, 

 according to the researches of Baron Cuvier, Marcel de Serres, 

 and others, are formed, first, of a cornea divided into a mul- 



reference to the digestive system of insects, in a series of excellent memoirs, 

 which have contributed to enrich the annals of natural sciences. M. Vic- 

 tor Audouinhas given a well-executed recapitulation of them in his article 

 Insects, in the '* Dictionnaire Classique d'Histoire Naturelle." 



* These are what I name homotenes, (alike to the end,) or the ametoholia 

 of Dr. Leach. 



f Its surface is divided into many regions, which are named the nose^ 

 the forehead, the vertex or lop, and the cheeks. The French term used 

 for the nose (chaperon) being equivocal, M. Latreille, has changed it to 

 epistoma or sub-mouth ; this part serves for the insertion of the labrum or 

 upper lip. 



N.B. Nose is the term given by Mr. Kirby — Ed. 



