SPONTANEOUS GENERATION. 291 



neous generation which would now be rejected as mon- 

 strous by the most fanatical supporter of the doctrine. 

 Shell-fish of all kinds were considered to be without 

 parental origin. Eels were supposed to spring sponta- 

 neously from the fat ooze of the Nile. Caterpillars 

 were the spontaneous products of the leaves on which 

 they fed; while winged insects, serpents, rats, and 

 mice were all thought capable of being generated with- 

 out sexual intervention. 



The most copious source of this life without an 

 ancestry was putrefying flesh; and, lacking the checks 

 imposed by fuller investigation, the conclusion that 

 flesh possesses and exerts this generative power is a 

 natural one. I well remember when a child of ten or 

 twelve seeing a joint of imperfectly salted beef cut into, 

 and coils of maggots laid bare within the mass. With- 

 out a moment's hesitation I jumped to the conclu- 

 sion that these maggots had been spontaneously gen- 

 erated in the meat. I had no knowledge which could 

 qualify or oppose this conclusion, and for the time 

 it was irresistible. The childhood of the individual 

 typifies that of the race, and the belief here enun- 

 ciated was that of the world for nearly two thousand 

 years. 



To the examination of this very point the cele- 

 brated Francesco Eedi, physician to the Grand Dukes 

 Ferdinand II. and Cosmo III. of Tuscany, and a mem- 

 ber of the Academy del Cimento, addressed himself 

 in 1668. He had seen the maggots of putrefying 

 flesh, and reflected on their possible origin. But he 

 was not content with mere reflection, nor with the 

 theoretic guesswork which his predecessors had founded 

 upon their imperfect observations. Watching meat 

 during its passage from freshness to decay, prior to the 

 appearance of maggots he invariably observed flies 



