x.] BIOGENESIS AND ABIOGENE8I8. 221 



the main concern of Harvey's wonderful little treatise is 

 not with generation, in the physiological sense, at all, but 

 with development ; and his great object is the establish- 

 ment of the doctrine of epigenesis. 



The first distinct enunciation of the hypothesis that all 

 living matter has sprung from pre-existing living matter, 

 came from a contemporary, though a junior, of Harvey, 

 a native of that country, fertile in men great in all 

 departments of human activity, which was to intellectual 

 Europe, in the sixteenth and seventeenth centuries, what 

 Germany is in the nineteenth. It was in Italy, and from 

 Italian teachers, that Harvey received the most important 

 part of his scientific education. And it was a student 

 trained in the same schools, Francesco Kedi a man of 

 the widest knowledge and most versatile abilities, 

 distinguished alike as scholar, poet, physician, and 

 naturalist who, just two hundred and two years ago, 

 published his " Esperienze intorno alia Generazione degl' 

 Insetti/' and gave to the world the idea, the growth of 

 which it is my purpose to trace. Redi's book went 

 through five editions in twenty years ; and the extreme 

 simplicity of his experiments, and the clearness of his 

 arguments, gained for his views, and for their con- 

 sequences, almost universal acceptance. 



Redi did not trouble himself much with speculative 

 considerations, but attacked particular cases of what was 

 supposed to be " spontaneous generation " experimentally. 

 Here are dead animals, or pieces of meat, says he ; I 



dicuutur ; non quod ex putredine oriunda sint, sed quod casu, naturae sponte, 

 et sequivoca (ut aiunt) generatione, a parentibus sui dissimilibus proveniant." 

 Again, in " De Uteri Membranis : " " In cunctorum viventium generatione 

 (sicut diximus) hoc soleune est, ut ortum ducunt a primordio aliquo, quod turn 

 niateriam turn efficiendi potestatem in se habet : sitque adeo id, ex quo et a quo 

 quicquid nascitur, ortum suum ducat. Tale primordium in animalibus (sive ab 

 aliis yenerantibus proveniant^ sive sponte, aut ex putredine nascentur} est humor 

 in tunica aliqua aut putami ne conclusus." Compare also what Redi has to say 

 respecting Harvey's opinions, " Esperienze," p. 11. 



