STAGES OF INSECT LIFE. 147 



disproportioned to those which have preceded it. To adduce 

 only a few examples : 



The great goat-moth,* while yet a caterpillar, occupies, in 

 solitary darkness, the trunk of willow, oak, and poplar. For 

 three successive summers it is employed in eating into the 

 solid wooden barrier which divides it from the sunny world 

 for as many winters it sleeps within one of the dark tunnels 

 thus excavated by its powerful jaws ; but after this extended 

 period of repletion and repose, it scarcely lives over the same 

 complement of weeks to exercise its broad, dusky pinions in 

 the summer moonlight. 



Other moths and butterflies remain various periods, but 

 frequently months, and sometimes years, in their aurelian 

 state of semi-torpor, while few of them are permitted to enjoy 

 their flitting delights for much longer than a fortnight. 



The same is exemplified in various beetles. The cock- 

 chafer, f as a grub or larva, first opens its eyes on the darkness 

 of a subterranean nest under the surface of a meadow, where, 

 with its numerous brood-brethren, it subsists (often to the 

 farmer's serious injury) upon the roots of grass. Unless un- 

 earthed by ploughshare, snout of swine, or bill of bird, the 

 grub of the chafer thus continues for four gloomy years work- 

 ing his covert mischief; but when arrived at the maturity of 

 his beetle form, he only feasts upon foliage, and travels, whir- 



* Cossus ligniperda. t Metolonfha wulgaris. 



VOL. III. 10. 



