SYSTEMATIC 

 ARRANGEMENT OF INSECTS. 



CLASS VIII. 

 INSECTA. 



ARTICULATE animals, with articulate feet. Head distinct, fur- 

 nished with two antennae. Heart situated in the back, similar to 

 a longitudinal vessel. Organs of respiration tubular, branched, 

 distributed throughout the whole body (tracheae). Sexes distinct. 



SECTION I. Apiropoda. 

 With numerous feet. With thorax not separate from abdomen. 



ORDER I. Myriapoda. 



Wingless. Feet numerous (24 or more), disposed according to 

 the length of the body, terminated by a single claw. Two clusters 

 of simple eyes, in various number ; in some no eyes. 



Myriapods. LEACH and other modern writers consider this order 

 as a class, and wish the name of Insects to be restricted to six- 

 footed articulate animals, of which the body consists of three prin- 

 cipal parts : head, thorax, and abdomen. Here there is no separa- 

 tion between thorax and abdomen, but the whole body is parted 

 into rings. The reason why we have placed these insects at the 

 beginning of the class, is to be found in their resemblance to the 

 ringed worms, to which they are related, not in their external form 

 alone, but also in their internal structure ; for even the six-footed 

 insects, which undergo complete metamorphosis, often in the larval 

 state approximate to the myriapods. We willingly admit, on the 

 other hand, that the myriapods accord with certain Crustaceans, and 

 even form an unconstrained transition to them. But this natural 

 transition is in some degree broken by other insects, which on the 



