8228 Notices of New Books. 



" Having prepared this sort of enclosure it commenced to spin its 

 cocoon in the interior, beginning near one of the extremities of the 

 major axis of the ellipse ; having agitated its head for two or three 

 moments with very great activity, I saw that one end of the cocoon 

 began to appear and already displayed its grooves. 1 observed the 

 construction attentively through a powerful glass, and I found that 

 the relief of the grooves arose from a row of angular meshes which 

 advanced one beyond the other and were fastened down by the threads, 

 which passing over these meshes were fastened on both sides to the 

 body of the cocoon ; between the intervals of each of these rows of 

 meshes I saw a very regular network of simple threads, which in 

 crossing formed a series of lozenges. The caterpillar continued this 

 work with surprising quickness, which prevented me from being well 

 able to follow its movements, and had spun in a few moments nearly 

 a third of the length of its cocoon. 



" Up to this time it remained entirely outside its cocoon, working 

 backwards like a ropemaker, but then it entered it head first, and 

 having turned round it protruded the anterior part of its body from 

 the open end of its cocoon, and having extended its head sufficiently 

 far, it commenced the other extremity of its cocoon, adopting a pro- 

 ceeding precisely similar to that which it had put into execution at the 

 opposite end. It continued to work thus till the space which was left 

 open between the two portions of the cocoon became so contracted that 

 the larva could no longer move its head ; then it withdrew entirely 

 within its cocoon, turned itself on its back, and, spinning from below, 

 so caused the two portions of the cocoon to approach each other that 

 at length they met; but since the ribs of the second portion of the 

 cocoon do not meet precisely in the same line with the ribs of the 

 other end, a break in their continuity is caused, as we have already 

 remarked. 



"All the work which I have just described was finished in about 

 half an hour, but it was not sufficient to shelter the larva from atmo- 

 spheric infiuences, nor from extraneous injury. The larva was then 

 only enclosed as in a prettj' cage, through which it might be easily 

 perceived ;. however, it soon set this to rights by spinning against the 

 interior of its cocoon till it was completely enclosed ; this occupied it 

 for some hours, and as I was then no longer able to see it, I know not 

 whether it continued to spin for a greater length of time. 



"When these cocoons are finished they have much consistence; 

 they are able to resist a moderate pressure, and one can no longer per- 



