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of some insect, whether out of the water or in it. Some eggs are 

 hatched in a few days after they are deposited, while many remain 

 during the winter, thus enabling the species to endure the rigors of a, 

 climate which otherwise would destroy them. 



As soon as hatched they enter the larva state, in which they do 

 most of their eating and all their growing ; in fact the whole object of 

 this stage of their life so far as the}' are concerned, is to eat and grow; 

 the great work of the perfect state being that of reproduction, "it is 

 during the larva state that they prove most injurious ; the army 

 worm, hessian fly, apple and peach borers, codling moth' and a host 

 of others commit all their depredations during this portion of their 

 existence. Most of the species of Lepidoptera are more or less injuri- 

 ous to vegetation, but all their injurious work is done while larvae, as 

 in the perfect state the long flexible mouth is incapable of inflicting 

 any injury on plants. 



Larvae are all wingless, and pass most of their time eating, growing 

 rapidly and frequently casting their skins, which process is called 

 moulting. This stage is generally much the longest portion of insect 

 life, some remaining in it for two, three, and even five years, as the 

 grubs of some beetles ; one species of cicada, the seventeen-year 

 locust, remains hid in the earth as a larva for seventeen years, 

 others pass through this stage in a few days or a few weeks at most, 

 as is the case with a large portion of the leaf-eating species. 



The forms of the larvae are very different in the different orders, 

 as will be seen when we come to examine more particularly the char- 

 acters of these orders. Some, as in most beetles, being grubs, some- 

 times with six small legs on the first three segments of the body, 

 while others are entirely footless. Others, as the larvae of most lep- 

 idoptera, are true caterpillars possessing from ten to sixteen legs, and 

 usually a very prominent head; others are headless, resembling mi- 

 nute earth-worms, while others are furnished with a prolongation like 

 a rat-tail ; some, as in most species, which do not undergo a complete 

 transformation, are similar in appearance to the perfect insects which 

 they produce. These illustrations will suffice to show the great dif- 

 ference between insects in this stage of their existence, yet as they 

 are constantly feeding and growing, it is not easy to fix upon any 

 characters which are permanent, and by which the various species 

 may be distinguished from each other; yet there are certain perma- 

 nent differences which enable us to determine the group of insects to 

 whice they belong, and which, combined with a knowledge of habits, 

 often enable us to name the species to which a given larva belongs. 



Many larvae, especially caterpillars, are furnished with false legs to 

 which the term pro-legs has been applied; these are short thick, fleshy 

 legs, not jointed or furnished with claws, as are the true legs, but a 

 broad, circular foot, surrounded by a fringe of minute hooklets. The 

 true legs are those situated on the three front segments, two on each 

 segment, and are usually furnished with a single claw ; the false or 

 pro-legs are situated, two and two, on one or more of the other seg- 

 ments ; those on the last ring or segment are usually called the anal 

 legs; those on the intermediate segments are thenibdominal legs. 



Although, as has been stated, insects, as a general and almost uni- 

 versal rule, deposit their eggs before they are hatched, yet there are 



