L ANIMALCULA OF INFUSIONS. 255 



art or accident efFeds in the one, and nature her- 

 ielf in the other, and the method by which it is 

 performed, we are ignorant of. Our beft micro- 

 fcopes give us no accefs to the interior of thefe 



animated 



divifion with an edged inftrument. When M. Bonnet 

 wrote to me, he was ignorant of this. Every one knows 

 his beautiful difcoveries on frelh water worms, which re- 

 produce themfelves when cut in pieces, Trnite d' InjeElolo' 

 gie, part 2. Muller has now obferved that they muhiply 

 by natural divifion, which M. Bonnet informed me laft 

 year, in thefe words : • Muller laft year fent me a fplen- 



* did work in quarto, illuftrated with figures, on infcfls 



* which are reproduced by fedtion or divifion both natural 



* and artificial. This work is unfortunately in German ; 

 ' and 1 could only learn his difcoveries by the tranflation 

 ' of fome paffages which a friend made viva voce. The 



* eftimable author has particularly repeated my obferva- 



* tions, publiflied 1744, part 2. of the Traiti d^lvfe^ologir^ 



* He confirms moft of them, and adds much of his own 



* enquiries. Among other things, he has feen the apodal 



* worms of frefh water multiply before his eyes by natural 



* divifion. He minutely defcribes this propagation, which 



* is very different from that of the clufter pol3'pus and 



* infufion animalcula. Behold, how thefe fingular genei- 



* rations extend more and more ! I had myfelf obferved 



* the fame in worms of the fame kind, but from igno- 

 ' ranee afcribed it to accidental caufes. The fadt is relate 



* ed in my Infeciohgie, * AnguUks de lean dowf.'-*^Thf) 



* clufter pol^'pus was then unkHovm to mc/ 



