22 THE INSECT WOULD. 



nearly always called a worm, or grub, and in certain cases, a cater- 

 pillar. 



Linnseus was the first to use the term "larva" taken from 

 the Latin word larva, "a mask" as he considered that, in this 

 form, the insect was as it were masked. At a certain period it 

 ceases to eat, retires to some hidden spot, and after changing its 

 skin for the last time, enters the third stage of its existence, and 

 becomes a chrysalis. In this state it resembles a mummy en- 

 veloped in bandages, or a child in its swaddling clothes. It is 

 generally incapable of either moving or nourishing itself. During 

 this period of its life the insect eats voraciously, and often 

 changes its skin. It continues so for days, weeks, months, and 

 sometimes even for years. 



While the insect is thus apparently dead, a slow but certain 

 change is going on in the interior of its body. A. marvellous work, 

 though not visible outside, is being effected, for the different 

 organs of the insect are developing by degrees under the covering 

 which surrounds them. When their formation is complete, the 

 insect disengages itself from the narrow prison in which it was en- 

 closed, and makes its appearance, provided with wings, and capable 

 of propagating its kind ; in short, of enjoying all the faculties which 

 nature has accorded to its species. It has thrown off the mask ; 

 the larva and pupa have disappeared, and given place to the per- 

 fect insect. 



To show the reader the four states through which the insect 

 passes in succession, in Fig. 16 is represented the insect known 

 as the Hydrophilus* firstly, in the egg state ; secondly, as the 

 larva, or caterpillar ; thirdly, in the pupa ; and fourthly, as the 

 perfect insect, or imago. The different degrees of transforma- 

 tion and evolution which we have just described, are those which 

 take place either completely or incompletely in all insects. Their 

 metamorphoses are then at an end. There are certain insects, 

 however, that show no difference in their various stages, except 

 by absence of wings in the larva ; and in these the chrysalis is 

 only characterised by the growth of the wings, which, at first 

 folded back and hidden under the skin, afterwards become free, but 

 are not wholly developed till the last skin is cast. These insects 



* A kind of water-beetle. ED. 



