216 TRUE TALES OF THE INSECTS. 



mature conditions await discovery ; and when success 

 does attend our efforts at protection, many examples are 

 probably observed of the depredations of the insidious 

 parasites. Not that failure to attain perfection is always 

 due to infestation of parasitic insects, as undoubtedly the 

 somewhat ponderous houses of the larvae render them to 

 a high degree impervious to the onslaughts of insect 

 enemies : the cause of death must be looked for else- 

 where. Death usually occurs after the larva has under- 

 gone metamorphosis, the pupa gradually shrivelling up 

 after assuming its proper form, nor can anything be 

 done, apparently, to avert the calamity. 



A Perpetual Prisoner. 



To return to the Case Moths' metamorphoses. The 

 female insect, as we have seen, unlike the male, is 

 destined never to desert the larval home. For her no 

 hour of emergence ever comes. When the pupa has 

 slept the appointed time, the unwieldy and almost 

 motionless moth feels little of the movement of on- 

 coming life then experienced by her lithe and lively 

 partner ; the animal, still resident within the habita- 

 culum formed by the larva, splits asunder the pupa skin, 

 and her transformations are complete : in some, at 

 least, of the species the female imago is continually 



