THE HJPA OR CHRYSALIS. 91 



however, sink gradually into a torpid state when 

 they are full grown, without making any prepa- 

 ration for the change, their secure situation render- 

 ing it unnecessary. This security occurs, especially 

 in the case of Bees, from each larva finding itself 

 in a cell prepared for it, even "before its birth, in 

 which to pass the first three stages of its life — that 

 of the egg, the larva, and the pupa. 



Most of the root-feeders seek no further pro- 

 tection than the hollow which they necessarily form 

 in eating their way through the substance on which 

 they feed. The larva of many Beetles thus undergo 

 their change either in old and rotten or in growing 

 wood, where they may be sought by the collector, 

 as their place of retreat will always be indicated by 

 the effect produced in their previous ravages. 



Others, in a less secure situation, appear to have 

 the instinct to protect themselves from accident 

 during their pupa state hy timely preparation ; hut 

 many of these, after a period of restlessness and 

 apparently a vague search, seem to content them- 

 selves, in despair of doing better, with a heap of 

 dead leaves or a slit in a tree, or beneath a flake of 

 decaying bark, where I have sometimes found hud- 

 dled together several chrysalides of the Bed-under- 

 wing Moth. Others seem at last to determine upon 



