Microscopical Essays, 327 



Ft generally prepares for the pupa ftate in the month of May ; 

 it's firft care being to find a hole in the tree fufficient to give iffue 

 to the moth : and if it finds none proper for the purpofe, it 

 makes one equal in fize to the future pupa. The hole being 

 made or found, it begins to conftruct a cafe or cone, which it 

 forms of thin pieces of wood, uniting them together, by filk, 

 into an ellipfoid fhape ; the outfide is formed of little flicks united 

 together in all directions ; the caterpillar takes care that the 

 pointed end of the cafe may be always oppofite to the mouth 

 of the hole : having finifhed the outride of the cafe, it lines the 

 infide with a filken tapeftry, of aclofe texture in all parts, except 

 the pointed end, and where the tiffue is loofer, in order to facilitate 

 it's efcape at a proper feafon. The work being finifhed, the cater- 

 pillar places itfelf in the cafe in fuch a manner, that it's head 

 may always lay towards the opening of the hole in the tree or 

 pointed end of it's cafe. 



In this ftate it remains at reft for fome time; the colour of the' 

 Ikin firft becomes pale, afterwards the whole {kin appears brown, 

 The interior parts of the head are detached from the (kull, the 

 legs retire or withdraw themfelves from their exterior cafe,, 

 the body fhortens, the pofterior part grows final 1, while the ante- 

 rior part fwells fo much, as at laft to burft the (kin, which, by a 

 variety of motions, it pufhes down to the tail, and thus exhibits 

 the pupa, in which the parts of the future moth may be eafily 

 traced. 



The covering of the pupa is at firft Toft, humid, and white, 

 but it foon dries and hardens, and is then of a marron colour ; 

 the fore-part, in which the lineaments of the head, the legs, and 



6 , the 



