29^ INSECTS. 



A new crop of hair grows between the old (kin and the new, and probably 

 helpji to throw off the external covering. 



The caterpillar begins at laft to prepare for its change into a chryfalis. 



It is probable all parts of the butterfly lay hid in the infedl, in its reptile 



Hate } and, when perfected, its firft great and principal change is into an 



aurelia, or chryfalis. Preparatory to this, it attaches itfelf to the ftalk 



or ftemof the plant, often voids even the internal meoibrane which lined 



its inteftines. Thofe which fpin a web, fet about that operation ; thofe 



which have already fpun, await the change in patience. When it has 



done fpinnin'g, it ftrikes in the claws of the two feet under the tail, and 



afterwards forces in the tail itfelf. If taken from the web they appear in 



great languor ; and, incapable of walking, thus they remain one or two 



days, preparing to change ; their bodies bent into a bow, which they 



occafionally ftraighten. As their change approaches, their body becomes 



more and more bent; their extenfions and convuifive contraftions more 



frequent. The animal quits the hinder part of its jfkin to drive itfelf up 



into the fore part, flill continuing to heave and work as before ; the fkull 



burfts into three pieces ; and an opening is made in the three firft rings, 



through which the infed: thrufts forth its naked body, with ftrong efforts, 



and gets free from its caterpillar 1km. Now the parts of the future 



butterfly are vifible; but fo foft, that the fmallefl: touch difcompofcs 



them. The animal is now become helplefs and motionlefs j waiting 



for the air to dry up its fuperficial moifture, and fupply it with a crufl: 



for reflfting injuries : it is now green. In ten or twelve hours its parts 



harden, its external covering becomes firm ; and in about four-and- 



twenty hours the chryfalis may be handled without danger. Such is the 



little pod or cone fo common by every pathway, flicking to nettles, and 



fometimes fliining like poliflied gold j whence its name, Chryfalis. 



Some mix fand with their gummy and moift webs, to (trengthen the 

 incruftarion ; others bury themfelves in the ground. Thofe that are to 

 remain in this ftate but a few days, choofe fome tender leaf, which they 

 render more pliant by difl'ufing a kind of glue on it : the leaf gradually 

 curls up, and withering as it enfolds, the infeft wraps itfelf within it. 

 Others fallen their tails to a tree, or to the firft worm-hole they meet in 

 a beam, and there wait. Such as are to lie feveral months in this ftate, 

 a£t with greater circumfpedion : either mix their web with fand, or 

 build deeper in wood. Such as prefer the leaves of willows, break their 

 tender twigs into fmall pieces, then pound them to powder ; and, by 



their 



