( 5i ) 

 it fome acute or corrofive fait, fitted for foftening the fliell of the 



egg- 



I cannot quit this part of the fubje^l, without exliibiting the for- 

 mation of the Silk- worm's egg, becaufe the feveral particles of which 

 it confifls, are fo firmly and clofely united together, that they pre- 

 I'erve the liquid fubfiance within the egg many months without the 

 leaft. evaporation. 



Plate II. fg. 25, FGH, is the fhell of the Silk-worm's egg, opened 

 by the animal, as it appeared to the limner through the microfcope ; 

 G H, is part of tlie aperture which the worm, by biting or gnawing, 

 opened for itfelf, and through which it crept out of the fhell. 



Some years after the precetling obfervations, I further profe- 

 cuted my enquiries by obferving the Silk-worms as they advanced in 

 growth, which I could eafily do, having two mulberry trees in my 

 garden, which fupplied me with food for the worms, of which I had 

 three or four hundred. 



I have often by the microfcope examined the cuticle or thin fkin 

 which is fhed by thefe infe6f:s the * lafl time before they are full 

 grown, and particularly the more folid part of it ^^•hich covers the 

 head ; and with great wonder, I beheld in it all the organs or mem- 

 bers with which the head is furniflied, and particularly I faw a num- 

 ber of eyes difpofed on each fize of the head, in fit order to enable 

 the animal to fee every objeil around it : further to examine which, 

 I have feveral times cut off the heads of full grown Silk-worms, for 

 otherwife they were in fuch continual motion, that I could not clearly 

 diflinguifli thefe eyes. When the Silk-worms were changed into 

 aurelias, I faw the fkins of their heads and the reft of their bodies, 

 which they had put off" on the change, and upon examining thefe by 

 the microfcope, I always found the horny coats of the eyes in their 

 caft-oft' fkins. Several parts or pieces of the head with the eyes in 



» Silk-worms fiicd their fkins four feveral times, before they begin to fyht their cone or 

 covering. 



