XXil HISTORICAL SKETCH. 



enunciation of the principle of natural selection is con- 

 cerned, it is quite immaterial whether or not Professor 

 Owen preceded me, for both of us, as shown in this 

 historical sketch, were long ago preceded by Dr. Wells 

 and Mr. Matthews. 



M. Isidore Geoffroy Saint-Hilaire, in his lectures 

 delivered in 1850 (of which a Eesume appeared in the 

 ' Kevue et Mag. de Zoolog.,' Jan. 1851), briefly gives 

 his reason for believing that specific characters "sont 

 fixes, pour chaque espece, tant qu'elle se perpetue au 

 milieu des memes circonstances : ils se modifient, si les 

 circonstances ambiantes viennent a chancer." "En 

 resume, V observation des animaux sauvages demontre 

 deja la variabilite limitee des especes. Les experiences 

 sur les animaux sauvages devenus domestiques, et sur 

 les animaux domestiques redevenus sauvages, la demon- 

 trent plus clairement encore. Ces memes experiences 

 prouvent, de plus, que les differences produites peuvent 

 etre de valeur generique" In his ' Hist. Nat. Generale ' 

 (torn. ii. p. 430, 1859) he amplifies analogous conclusions. 



From a circular lately issued it appears that Dr. 

 Freke, in 1851 (' Dublin Medical Press,' p. 322), pro- 

 pounded the doctrine that all organic beings have 

 descended from one primordial form. His grounds of 

 belief and treatment of the subject are wholly different 

 from mine ; but as Dr. Freke has now (1861) published 

 his Essay on the ' Origin of Species by means of 

 Organic Affinity,' the difficult attempt to give any idea 

 of his views would be superfluous on my part. 



Mr. Herbert Spencer, in an Essay (originally pub- 

 lished in the ' Leader,' March, 1852, and republished in 

 his ' Essays/ in 1858), has contrasted the theories of the 

 Creation and the Development of organic beings with 



