i3uTLEE. — On the Butterflies of New Zealaiul. 2G7 



" As soou as the larva is full grown it spins a little tuft of silk to tlie - 

 under side of wliatever object it may he resting upon, and after entangling 

 the hooks of its hind legs in this silk it lets go the hold of its other legs and 

 hangs down, with the head and anterior joints of the body curved. In this 

 position it hangs for about twenty-four hoiu'S, during which the fluids of 

 the body naturally gravitate towards the upturned joints, until the latter 

 become so swollen that at last, by a little effort on the part of the larva, 

 the skin bursts along the back behind the head. Through the rent thus 

 made the anterior portion of the pupa is protruded, and by constant 

 stretching and contracting the larval skin is slipped and crowded backwards 

 until there is but a small shrivelled mass gathered around the tail. Now 

 comes the critical period — the culminating point. 



" The soft and supple chrysalis, yet showing the elongate larval form 

 with distinct traces of its prolegs, hangs heavily from the shrunken skin. 

 From this skin it is to be extricated and firmly attached to the silk outside. 

 It has neither legs nor arms, and we should suppose that it would inevitably 

 fall while endeavouring to accomplish this object. But the task is performed 

 with the utmost surety, though appearing so perilous to us. The supple 

 and contractile joints of the abdomen are made to subserve the purpose of 

 legs, and by suddenly grasping the shrunken larval skin between the folds 

 of two of these joints as with a pair of pincers, the chrysalis disengages the 

 tip of its body and hangs for a moment suspended. Then with a few 

 earnest, vigorous, jerking movements it succeeds in sticking the horny point 

 of its tail into the silk, and firmly fastening it by means of a rasp of minute 

 claws with which that point is furnished. Sometimes severe effort is needed 

 before the XDoint is properly fastened, and the chrysalis frequently has to 

 cHmb by stretching the two joints above those by which it is suspended, and 

 clinging hold of the shrivelled skin further up. The moment the point is 

 fastened the chrysalis commences, by a series of violent jerkings and 

 whu-hngs, to dislodge the larval skin, after which it rests from its eflorts and 

 gradually contracts and hardens. The really active work lasts but a few 

 minutes, and the insect rarely fails to go through with it successfully. The 

 chrysalis is a beautiful object, and as it hangs pendent from some old 

 fence-board or fi'om the under side of an Asdepias leaf, it reminds one of 

 some large ear-drox3 ; but, though the jeweller could successfully imitate 

 the form, he might well despair of ever producing the clear pale-green and 

 the ivory-black and golden marks which so characterize it. 



" This chrysahs state lasts but a short time, as is the case with all those 

 which are known to suspend themselves nakedly by the tail. At the end 

 of about the tenth day the dark colours of the future butterfly begin to 

 show through the delicate and transparent skin, and suddenly this skin 



