86 INSECTS. 



state, it seems to be lifeless, having neither a distinct head nor 

 moveable limbs, after a lapse of time the chrysalis skin bursts 

 open, and from the rent issues a butterfly, whose wings, soft and 

 crumpled at first, soon extend and harden, and become fitted to 

 bear away the insect in search of the honied juices of flowers. 

 Hence there are three distinct periods in the life of an insect, more 

 or less distinctly marked. In the first, or period of infancy, an 

 insect is technically called a larva, a word signifying a mask, be- 

 cause therein its future form is more or less masked or concealed. 

 This name is equally applied to grubs, caterpillars, and maggots, 

 and to all young insects before their wings .begin to appear. Con- 

 sequently, in this first period, which is much the longest portion 

 of their lives, insects are always wingless, pass most of their time 

 in eating, grow rapidly, and, to allow of their growth, repeatedly 

 cast off their skins. 



During the second period some insects retain their activity and 

 their appetite for food, continue to grow and acquire the rudi- 

 ments of wings ; while others, at this age, entirely lose their larva 

 form, take no food, and remain at rest in a death-like sleep. This 

 is called the pupa * state of the insect, because in this condition 

 they resemble an infant wrapped in swaddling-bands. The pupae 

 from caterpillars are more commonly called chrysalids, because 

 some of them, as the name implies, are gilt or adorned with golden 

 spots, whereas pupae that retain their legs and capability of loco- 

 motion are often named nymphs, the reason for which is not very 

 obvious. 



At the end of the second period insects again shed their skin, 

 and come forth fully grown, and (with few exceptions) provided 

 with wings. They thus enter upon their last or adult state, wherein 

 they no longer increase in size, and during which they provide 

 for their progeny. This period only lasts a short time, for most 

 insects die immediately after they have laid their eggs. Bees, 

 wasps, and ants, however, which live in society, and labour to- 

 gether for the common good, .continue much longer in the adult 

 state. 



The innumerable races of insects may be classified in accord- 

 dance with the following table : 



* Pupa, a baby. Those who have seen infants in many parts of the Continent tied 

 tight to a board, will appreciate the appropriateness of the expression. 



