( -^3 ) 



to be feen, but alfo a blood veflel, diftinctly appenring to be coni- 

 pofed of annular parts, in which manner the blood veflels of 

 Fleas and other infects are formed, fimilar to the afpera arteria, 

 or the wind, pipe in the lungs of animals. And at one time, hav- 

 ing a Flea fixed by its hind part to the point of a needle, licfore 

 the microfcope, I faw throughout the whole length, on each fide 

 of this joint, as between E F and L K, and alfo, in the middle of 

 it, a wonderfully fwift motion or current of the juices, which ap- 

 peared to me the plainer as there were globules mixed with thofe 

 juices : but I did not notice this motion, except at the time the 

 Flea was moving its leg or foot, and then this motion continued 

 for fome time after the leg and foot were at reft. Many perfons 

 viewing this would fay, that they had feen the circulation of tlic 

 blood in the Flea's foot. 



Moreover, upon the motion of the leg, as well in this joint as in 

 the others, there was fo great an agitation of the component 

 parts as is inconceivable. This agitation, I concluded, was only 

 caufed in the fleshy mufcles of the leg, becaufe it partly continued 

 after the death of the Flea ; but it was impoflible for the limner 

 to imitate, in his drawing, all the parts he faw: and he often, while 

 making the drawing of this leg and the other parts of the animal's 

 body, broke out into an exclamation, " Heavens! what wonders 

 here are in fo fmall a creature!" 



F G I K is the third joint of the leg, in which may be feen many 

 fharp-pointcd particles, kicking out like thorns. 



At G H I are Ihevvn the five laft or fmallert joints of the Flea's 

 leg, all formed in the fame manner ; and here plainly appears how 

 all thefe joints mutually depend upon, and are fubordinate to, 

 each other. 



At II arc two perfectly formed claws : w ith thefe every one of 

 the feet is fumifiicd, and the Flea ufi^s them M'ith fuch wonderful 

 fwiftnefs and dexterity, that though when fiiut up in the glafs he 

 leaps about, and touches only a fmall particle of dirt or impurity, 



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