92 THE BUTTERFLY VIVARIUM. 



burying themselves at a considerable depth in the 

 earth, as the most secure position in which to un- 

 dergo their change, and often make themselves a 

 kind of vault, by consolidating the surrounding 

 soil with a mucous fluid. The larva of the Meat- 

 fly quits the scene of its repast when full grown, 

 and seeks at some considerable distance a fit place 

 for its change ; but a heap of dust, or any kind of 

 dry rubbish, generally suits its purpose, as it is 

 not particularly fastidious in its choice. 



Many, having found what appears to them a 

 suitable retreat, take no more precautions, like those 

 whose position is naturally secure at the time, from 

 the nature of their habits. Others, like the larvae 

 of the Syrphm and Lady-bird tribes, merely secure 

 themselves by a few threads, spun at the caudal 

 extremity, by means of which they remain firmly 

 attached to the leaf they have selected as the scene 

 of their transformation, in the position in which 

 the chrysalis of Chrysomela Tremulce is represented 

 in Plate VII. No. 6. 



Some small insects, as Harpya Fagi, masticate 

 portions of wood from the tree on which they feed, 

 for the purpose of forming a pupa-house, mixing 

 with it a fluid furnished by the mouth, which causes 

 the composition to solidify very rapidly, and the 



