THE NATURE OF METAMORPHOSIS. 6/ 



skeleton This is what takes place in lepidopterous insects. 

 Some of the Coleoptera, as in the instance of Melolontha vulgaris, 

 the common Chaffer Beetle, remain for a greater length of tmie 

 in their nests before they come abroad, after entering the imago 

 state This is also the case with the humble-bees. When 

 these insects first come from their cells they are exceedmgly 

 feeble their bodies are soft, and covered with moisture, their 

 thick 'coating of hairs has not acquired its proper colour, but 

 is of a greyish white, and they are exceedingly susceptible of 

 diminished warmth. They crowd everywhere among the cells and 

 near other bees, where there is most warmth. In a few hours 

 this great susceptibility is diminished, and their bodies acquire 

 their proper colours, but they do not become sufficiently strong to 

 be capable of great muscular exertion, and undertake the labours 

 of the nest, until the following day. When an insect has once 

 entered its perfect state, it is believed to undergo no further meta- 

 morphosis or change of covering. But there exists an apparent 

 exception to this general law in the Ephemcridce, which are noted 

 for the shortness of their existence in the imago state. When 

 these insects have crept out of the water and rid themselves of the 

 pupa covering, and their wings become expanded, they soon take 

 flight, but their first movements in the air are performed with some 

 difficulty, and they shortly alight again and throw off a very deli- 

 cate membrane with which every part of the body has been 

 covered, and then resume their flight with increased activity. The 

 condition of the insect previous to this final change has been 

 called the pseud-imago state." 



The structural changes which occur during metamorphosis are 

 certainly equalled, in the interest they must excite, by the psy- 

 chical ; and the habits, instincts, and passions witnessed during 

 the difl"erent phases of existence are indeed most diverse. 



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