ON GENERATION. 191 



« 

 From this and other analogies, Mr Ncedham 

 concludes, that the fpermatic worms of other 

 animals, it is reafonable to think, are only or- 

 ganic bodies ; a fpecies of machines fimilar to 

 thofe of the calmar, which ad at different times ; 

 for, iays he, if w^e fuppofe that, of the prodi- 

 gious number of fpermatic animalcules which 

 appear in the field of the microfcope, only a few 

 thoufands ad: at a time, this w^ill be fuflicient to 

 make us believe the whole to be alive. If it be 

 farther fuppofed, he adds, that the motion ot 

 each animalcule lalls, like that of the calmar 

 machines, about halt a minute ; in this cale, the 

 fucceffive action of the fmall machines would 

 continue for a confiderable time, and the ani- 

 malcules W'Ould die one after another. Befides, 

 why Ihould the femen of the calmar alone con- 

 tain machines, while that of all other animals 

 contain real living animalcules ? Here the ana- 

 logy IS fo ftrong as to be almoft irreliRible. Mr 

 Needham farther remarks, that even Leeuwen- 

 hoek's experiments feem to indicate that the 

 fpermatic animals have a great refemblance to 

 the organic bodies in the femen of the calmar. 

 Speaking of the femen of the cod, Lceuwen- 

 hoek remarks, that he imagined the oval bodies 

 to be animalcule^ burft and diftended, becaufe 

 they were four jtimes larger than when ahve. 

 And, in another place, he obfervcs of the femen 

 of a dog, that the animalcules often changed 



their 



