THEORY OF EVOLUTION 29 



the species, but rather the escape of the species 

 from the old into a new world. 



If then we recognize the intimate bond in 

 chemical constitution of living things and of the 

 world in which they develop, what is there im- 

 probable in St. Hilaire's hypothesis? Why, in 

 a word is not more credit given to St. Hilaire 

 in modern evolutionary thought ? The reasons 

 are to be found, I think, first, in that the evi- 

 dence to which he appealed was meagre and 

 inconclusive; and, second, in that much of his 

 special evidence does not seem to us to be ap- 

 plicable. For example the monstrous forms 

 that development often assumes in a strange 

 environment, and with which every embryolo- 

 gist is only too familiar, rarely if ever furnish 

 combinations, as he supposed, that are capable 

 of living. On the contrary, they lead rather to 

 the final catastrophe of the organism. And 

 lastly, St. Hilaire's appeal to sudden and great 

 transformations, such as a crocodile's egg 

 hatching into a bird, has exposed his view to too 

 easy ridicule. 



But when all is said, St. Hilaire's conception 

 of evolution contains elements that form the 



