LIMENITIS SIBYLLA. 39 



few times, then stretches itself downwards in a long 

 attenuated line, which causes a rupture of the skin close 

 to the head ; the skin then is seen slowly to ascend, 

 exposing the bare and soft shining parts below, from 

 which a flat and forked pair of horns grow out per- 

 ceptibly as one beholds this wonderful process ; the 

 skin continues to glide slowly upwards, and as the soft 

 parts become exposed they are seen to swell out later- 

 ally and to assume the very singular projections so 

 characteristic of this chrysalis, the skin of the old head 

 gliding up the belly marks the progress of the disclosure 

 as the colour of the old and new surfaces is at this time 

 alike, the new being, however, rather more shining 

 and transparent. 



Occasionally during the bulging out of the soft parts, 

 a kind of convulsive heave or two occurs, but other- 

 wise it remains still until the creature is uncovered as 

 far as the ninth or tenth segment, it then curves its 

 anal extremity by a sudden twist laterally, and in a 

 moment dexterously withdraws the tip of the anal seg- 

 ment from the larval prolegs by an opening on the 

 back of the skin at that part. At this critical moment 

 one has time to see that the naked shining point is 

 furnished with black hooks, and to apprehend a fall, 

 but in another moment the pupa has forcibly pressed 

 the curved tip with its hooks against the stem close to 

 the previous attachment of the anal prolegs, and now 

 it is strongly and securely fixed. 



The creature now seems endowed with wonderful 

 power and vigour, it swings boldly to and fro, and un- 

 dulates itself as if to gain longer swings, when presently 

 the old skin that remains is seen to burst away and 

 fall off, the chrysalis gradually becoming quiescent. 



The entire metamorphosis from the first waking to 

 the last movement, occupied nearly seven minutes. 

 In sixteen days the perfect insect emerged. 



The chrysalis is very angular, and its wing-cases 

 very projecting, the dorsal surface of the thorax rises 

 to a prominent ridge, and a little beyond it is a flat, 



