( 40 ) 



Fig. 14, MNO PQ, reprefent the pellicle put off by the mag- 

 got, when it changed into a chr^'falis, leaving the wrinkles in it as 

 they here appear ; and at M are the places where the maggot's 

 horns flood. 



Three days after this drawing had been made, I faw that the 

 •chryfalis was very much altered, and many parts appeared in it which 

 till then could not at all be diftinguilhed ; therefore I caufed a draw- 

 ing to be made of this alfo, to Ihew fuch alteration. 



Fig. 15, A S T V, is this drawing, taken as exactly as the limner 

 was able to reprefent this fecond appearance of the chryfalis. 



Fig. 16, ABCDEFGHIKLMN, reprefents an entire Flea, 

 glued by tlie back to the point of a needle, and fo placed before 

 the microfcope, but being tirll killed, becaufe it would be impoffible 

 to make a drawing of a Flea while alive. Nor, indeed, did I intend 

 to have given a drawing of the whole Flea, but a certain learned 

 gentleman ftrongly urged me to it, faying, that the world would 

 thereby be more convinced, that Fleas arc not produced from cor- 

 ruption, but in the ordinary way of generation, and I therefore 

 complied with his request. In this animal a great number of blood 

 vessels were to he seen, particularly in the belly, but the limner 

 only drew a few of them, faying, that it was not in his power to 

 imitate the remainder in his drawing. 



This Flea appeared to me, through the fame microfcope, eight 

 times larger than here lliewn, though the limner declared that it 

 did not feem any larger to him. Nor could I ever have believed 

 that there was fuch a diverfity in the fight of different people as I 

 now find to be the cafe. But this limner was very fliort fighted. 



At D E F are fhewn the hind feet ; F G H the middle feet ; and 

 1 KL the fore feet ; placed on the head : and between thefe lie the 

 organs or weapons witli which the Flea pierces or bites, and feeks 

 its food. L M N are two horns on the Flea's head. 



I had formerly figured to myfelf the manner in which Fleas must 

 .get their food out of the bodies of men and animals ; but becaufe 



