( 39 ) 



about our houfes, but they are immediately found out by mites who 

 come to feed upon them ; and, in the prefent cafe, though I thought 

 I had perfe6lly fecured thefe maggots from the mites, becaufe the 

 glafs tube wherein I had put them, which was ahnoll an inch in dia- 

 meter, and five inches long, was fo clofely Hopped at each end with 

 cork, that I fliould have thought it impoffible for any mite to get 

 in ; yet now I found the contrary to be the cafe : and indeed, I 

 have often found mites feeding on things in places where I won- 

 dered they could fo foon discover their food. And now, upon 

 feeing thefe mites about the maggots, it occurred to my thoughts, 

 whether or no thofe fmall and very flender prominent parts in the 

 maggot, which m Jig. 10, are Ihewn at A, might not be weapons 

 designed for its defence againft the mite. 



But the web fpun by the maggot, and wherein it inclofes itfelf, 

 before its transformation, proted:s it in that Hate from all attacks of 

 the mite ; and the like we may conclude, to be the cafe with the 

 filk worm, which while in its Hate of tranfmutation into a butter- 

 fly, is protected by its cone or cafe, not from mites, but from 

 birds ; and this I am well allured is the cafe with all caterpillars, 

 which when of full growth, and the time of their tranfmutation 

 approaches, do inclofe themfelves in fome kind of web, or co- 

 vering. 



The maggot which I have faid I faw changed into a chryfalis, I 

 the next morning placed before a microfcope, and delivered it to 

 the limner, to make a drawing of it. 



Fig. 13, A B C D E F, is this chryfalis ; A K, are the horns of the 

 yet unformed Flea ; L G B, is one of its fore legs, which rife out 

 of the head at L ; and herein, at B, may be feen all the Imall 

 joints which will be found in the legs and feet when perfectly 

 formed : the like joints may alfo be feen in C and D. 



H C is one of the middle feet, and at G may be ieen that the 

 fore feet partly cover the middle feet, and thefe in part cover the 

 hind feet ; I D and C H are the two hind feet, which are in part 

 covered by the middle ones. 



