170 INSECTS. 



the parent insect, others are covered with a coat of 

 hair, others are glued to the leaves of plants, so that 

 they may not be shaken off by the wind, nor washed 

 off by the rain. Some insects make incisions in the 

 leaves of vegetables, depositing an egg in each in- 

 cision ; others envelope their eggs in a soft substance 

 which forms the first aliment of the young ; and 

 others make a hole in the earth, and, having stored 

 it with a sufficient quantity of proper food, deposit 

 their eggs in it. 



Many of the insects which have their wings co- 

 vered with scales pass the winter in the pupa or chry- 

 salis state ; in fact all that feed on annual plants do 

 so ; for, as these plants die in the autumn, and may 

 spring up again in the ensuing year, from seed, in 

 another place, the eggs deposited on them in autumn 

 could hardly escape destruction. Even were the 

 larvae or caterpillar hatched before winter, and had 

 the power of hybernating in that state they would 

 have no certainty of being in the neighbourhood of 

 their appropriate food the next spring. By wintering 

 in the pupa state, these accidents are provided against. 

 In many ways the chrysalides are extremely tenacious 

 of life. Reaumur states that he subjected some to 

 a degree of cold below freezing, until each chrysalis 

 became a solid brittle mass of ice, nevertheless they 

 produced the perfect insect in due time. 



Most of the butterflies and moths, which come 

 forth in the spring or summer, perish or disappear at 

 the approach of winter. There are but few whose 

 period of life exceeds that of a year. 



When the insect has quitted the exerviee of the 

 pupa, it has attained the last stage of its existence, 

 and is termed an Imago or perfect insect. After its 

 first exclusion it is weak, soft, and languid ; and all 

 its parts are covered with moisture. The wings, 

 instead of having the amplitude which we generally 

 perceive, are very small, and of a dull colour, in 

 which no distinct characters can be traced. These 

 symtoms of debility and imperfection soon vanish ,* 



