SECT. XXXIX. 3- GENERATION. 555 



held by fome philofophcrs) has no fupport from ex- 

 periment or analogy. 



III. i. Many ingenious philofophers have found 

 fo great difficulty in conceiving the manner of the 

 reproduction of animals, that they have fuppofed 

 all the numerous progeny to have exifted in minia- 

 ture in the animal originally created ; and that thefe 

 infinitely minute forms are only evolved or diftend- 

 cd, as the embryon increafes in the womb. This 

 idea, befides its being unfupported by any analogy 

 we are acquainted with, afcribes a greater tenuity 

 to organized matter, than we can readily admit ; as 

 thefe included embryons are fuppofed each of them 

 to confift of the various and complicate parts of ani- 

 mal bodies; they muft poflefsa much greater degree 

 of minutenefs, than that which was afcribed to the 

 devils that tempted St. Anthony ; of whom 20,000 

 were faid to have been able to dance a faraband on 

 the point of the fineft needle without incommoding 

 each other. 



2. Others have fuppofed, that all the parts of the 

 embryon are formed in the male, previous to its 

 being depofited in the egg or uterus ; and that it is 

 then only to have its parts evolved or diftended as 

 mentioned above ; but this is only to get rid of one 

 difficulty by propoiing another equally incompre- 

 hcnfible : they found it difficult to conceive, how 

 the embryon could be formed in the uterus or egg, 

 and therefore wifhed it to be formed before it came 

 thither. In anfwer to both thefe doctrines it may 

 be obferved, ift, that fome animals, as the crab- 

 fifli, can reproduce a whole lirnb, as a leg which 

 has been broken off; others, as worms and fnails, 

 can reproduce a head or a tail, when either of them 

 has been cut away ; and that hence in thefe animals 

 at lead a part can be formed anew, which cannot be 

 fuppofed to have exifted previouily in miniature. 



VOL. I. O o Secondly, 



