202 



Microscopical Essays, 



refilling external injuries ; a cafe, which is at the fame time the 

 fepulchre of the caterpillar, and the cradle of the moth ; where, 

 as under a veil, this wonderful transformation is carried on. 



1'he pupa has been called a chryfalis, or creature made of gold, 

 from the refplendent yellow colour with which fome kinds are 

 adorned. M. de Reaumur has (hewn us whence they derive this 

 rich colour ; that it proceeds from two {kins, the upper one a 

 beautiful brown, which lays upon or covers a nighly-polifhed 

 and fmooth white fkin : the light reflected from the lad, in paffmg 

 through, gives it the golden yellow, in the fame manner as this 

 colour is often given to leather ; fo that the whole appears gilded, 

 although no gold enters into the tincture. The chryfalis of the 

 common white butterfly fu mimes a mod beautiful object for the 

 lucernal opake microfcope. 



Thofe who are defirous to difcover diflindlly the various mem- 

 bers of the moth in the pupa, mould examine it before the fore- 

 mentioned fluid is dried up, when it will be found to be only the 

 moth, with the members glued together ; thefe, by degrees, ac- 

 quire fufficient force to break their covering, and difengage them* 

 felves from the bands which confine them. 



To examine the moth concealed under the fkin of a caterpillar, 

 one of them mould be taken at the laft change ; when the ikirr 

 begins to open, it mould be drowned in fpirits of wine, or fome 

 ftrong liquor, and be left therein for fome days, that it may 

 take more confiftency and harden itfelf ; the (kin of the cater- 

 pillar may then be eafily removed : the chryfalis, or feeble moth, 

 will be firft difcovered, after which the tender moth may be 



traced : 



