THE ORIGIN OF SPECIES 545 



comparison of the phylogenic and the embryonic succession/' and in 

 the resultant principle that " the laws of embryonic development 

 (ontogeny) are also the laws of geologic succession." This method 

 and this principle Le Conte represented as " added " to biology by 

 Agassiz. Holding such views of the importance and the date of origin 

 of the recapitulation theory, Le Conte concluded that no one was 

 reasonably entitled to believe in the transformation of species prior to 

 the publication of the work of Agassiz; and hence that Chambers's 

 evolutionism was a " baseless speculation." 39 Le Conte's popular book 

 has done much to form current ideas on this subject. But its author 

 was misled by piety towards the memory of his greatest teacher into a 

 serious neglect of chronology, in a matter where chronology is of the 

 essence of the question at issue. Even if Agassiz be regarded as the 

 originator of the doctrine of recapitulation, it must be remembered that 

 he announced his evidences for that doctrine in his " Poissons du vieux 

 gres rouge," 1842-44, and repeated them in popular form in his Lowell 

 Lectures of 1848. 40 And in point of fact, the doctrine and an impor- 

 tant mass of evidence for it had then long been familiar; so that one 

 finds Lyell, before 1835, arguing against the use of it as* a proof of 

 evolution. In the " Principles of Geology," 41 he wrote : 



There is yet another department of anatomical discovery to which I must 

 allude, because it has appeared to some persons to afford a distant analogy, at 

 least, to that progressive development by which some of the inferior animals 

 may have gradually been perfected into those of more complex organization. 

 Tiedemann found, and his discoveries have been most fully confirmed and 

 elucidated by M. Serres, that the brain of the foetus assumes, in succession, forms 

 analogous to those which belong to fishes, birds and reptiles before it acquires 

 the additions and modifications peculiar to the mammiferous tribe. So that in 

 the passage from the embryo to the perfect mammifer, there is a typical repre- 

 sentation, as it were, of all those transformations which the primitive species 

 are supposed to have undergone, during a long series of generations, between 

 the present period and the remotest geological era. 



Lyell's reply to this argument was brief and dogmatic : he fully ad- 

 mitted the facts, but denied the inference. 



It will be observed that these curious phenomena disclose, in a highly inter- 

 esting manner, the unity of plan that runs through the organization of the 

 whole series of vertebrated animals; but they lend no support whatever to the 

 notion of a gradual transmutation of one species into another ; least of -ill, of the 

 passage, in the course of many generations, from an animal of a more simple 

 to one of a more complex structure. 



To the mind of Darwin the same sort of data presented a very dif- 

 ferent import. 



89 Le Conte, " Evolution in its Relation to Religious Thought," 2d ed., 1905, 

 ch. II.: The Relation of Louis Agassiz to the Theory of Evolution. 



40 Cf . Agassiz's own words, cited in Marcou, " Louis Agassiz," I., 230 ; and 

 Morgan, "Evolution and Adaptation," p. 61. 



"First American edition, 1837, I., 526. 



