INSECT A. 719 



on this occasion, by merely noting the different orders and their character- 

 istics, after we have mentioned some of the attributes common to all 



The term " insect " means cut into or divided, and so the insecta are 

 divided, as already mentioned, into three parts, head, thorax, and abdomen, 

 the thorax being subdivided into three rings, /r<?-thorax, ;;/*j0-thorax, and 

 ?;/to-thorax beginning, middle, and end. All insects have six legs, and 

 usually two or four wings, though some have no wings at all. The legs are 

 united to the thorax, the antennae and eyes to the head. The abdomen 

 contains the important sexual organs, a sting or defensive weapon, and in 

 females the egg chamber. 



Insects breathe by tubes in the sides, and consume a great quantity of 

 air. Their powers of flying and leaping are too familiar to need dwelling 

 upon. The wings display beautiful colours like those observable in the 

 soap-bubble, others are covered with scales or hairs. The mouths vary very 

 much with the species, as the manner of obtaining food is by suction or 

 gnawing. The blood of insects is pale and thin. 



The various transformations which insects undergo are always a subject 

 of interest for the young student. The ugly forms which develop in 

 beautiful creations are more astonishing than the change of the " ugly duck- 

 ling" into the graceful swan. 



JL 



Fig. 848. Larva. Fig. 849. -Pupa. 



Insects come to maturity only after undergoing successive changes 

 from the egg to the perfect animal. The eggs (some of which are very 

 beautiful) are first deposited in some safe place, either attached to a leaf or 

 tied up in a small bundle by silken threads spun by the parent insect, and in 

 some nutritious substance, so that when it comes to life it may at once have 

 food ; this is sometimes in manure, sometimes in flesh, and sometimes under 

 the skin of a living animal (few are exempt from this infliction), where they 

 remain for a time and then come forth as maggots, caterpillars, etc. ; in this 

 state they are called larva, these are generally active creatures and eat most 

 voraciously, which seems to be the principal act of this state of their exist- 

 ence. These larvae frequently change their skins as they grow, and at last 

 they assume the next stage of their life, the pupa or chrysalis state, which is 

 one generally of complete inactivity ; many of these larvre weave themselves 

 a covering of a sort of silk, to defend them while in the pupa state, such 

 as the silkworm, whose covering (cocoon) is the source of all the silk of 

 commerce, others merely place themselves in a situation of security. The 

 pupa remains dormant for a Certain time, and then becomes the imago or 

 perfect insect (the last state of its existence), such as a moth, a butterfly, a 

 beetle, etc. These arc of different sexes, and in due time produce a batch 



