DIFFERENT SYSTEMS. 127 



this chain of infinite individuals contained in 

 one be incomprehenlible to us, it is entirely 

 owing to the imbecillity of our minds, of which 

 we have daily proofs. But it is not, therefore, 

 lefs confonant to truth, that all the animals which 

 have exifted, or can exift, were created at once, 

 and were all included in their firfl mothers. The 

 relemblance of children to their parents is owing, 

 he continues, to the imagination, which acts fo 

 forcibly on the foetus as to produce ftains, mon- 

 ftrofities, diforder of parts, and extraordinary 

 concretions, as well as perfect limilarities. 



This fyftem of eggs, though it explains no- 

 thing, and has no foundation in Nature, would 

 have obtained the univerfal fufFrages of phyfi- 

 cians, if, nearly about the fune time, another 

 opinion had not fprung up, founded upon the 

 difcovery of fpermatic animals. 



This difcovery, which we owe to Leeuwen- 

 hoek and Hartfoeker, was confirmed by Andry, 

 Valifnieri, Bourguet, and many other obfervers. 

 I fhall relate what has been advanced concern- 

 ing thofe fpermatic animals which are found in 

 the femcn of all males. Their number is fo 

 great, that the femen feems to be entirely com- 

 pofed of them; and Leeuwenhoek pretends to 

 liave feen many millions of them in a drop lefs 

 than the fmalleft grain of fand. Though none 

 of them appear in females, they are found in the 

 emitted femen of all males, in the tefticles, and 

 in the veficulae feminales. When the femen of 



a 



