( H3 ) 



two, three, four, and fome as many as fcven or eight cavities 

 in it, each cavity containing a fhort, white aurclia, or chryfahs, 

 formed of many joints like rings; thefe aurehas were ahnofl: all 

 alive, and I judged tliem to have been produced from maggots, 

 tlie offspring of fome fly or iuch like infect, which had laid its 

 egg on the thiftle ; and that thofe maggots having pierced the 

 vcllels of the thiftle, while in the flourifliing time of its growth, 

 had occafioned a copious effufion of juices, by means of which a 

 tumor or fwelling had been formed upon the tliillle, which had 

 inclofed the maggot, and formed a folid fubftance round it. And 

 upon further profecuting this fubjedl, to elucidate my own pofi- 

 tion that thefe nuts had been produced by means of maggots, I 

 opened feveral of them at different times in the fucceeding winter, 

 preferving the aurelias ; and at length, towards the end of the 

 April following, they produced a fpecies of black flies, different 

 from any I had before fcen, for the hind part of their bodies ter- 

 minated in a point, forming a kind of fheath, wherein was con- 

 tained a fmall fling. 



I thought it would not be amifs, to exhibit to the view, the 

 fliapc and make of thefe nuts, in order to fliew tlic fizes of thein 

 and of tlie cavities they contain ; and alfo how -far, fancy and 

 imagination will go with fome people. 



Plate V. fg. 22, 23, 24, reprefent three of thefe thiftle-nuts 

 dried, and of different flzes. 



Fig. 25, is one of the fame nuts, cut open on the fide, where 

 may be ^een two cavities, one of them, at A, containing an aurelia. 



Fig. 26, is the fly produced from this aurelia. 



Fig. 27, is a tliiftle-nut cutacrofs, fliev>ing feven ca\itics, wherein 

 the aurelia had Iain, 



END OF THE FIRST PART. 





