THE CLASSIFICATION OF THE VERTEBRATA. 179 



tlie waj' is paved for the appreciation of the whole animal 

 kingdom as a unity, consisting of beings derived from 

 ova, by comparable stages, exhibiting as one may say an 

 orderly evolution both in its totality and in the individuals 

 of each species. In fact such a conception was in a certain 

 fashion elaborated by Oken and his follower Cams, not to 

 mention others, even at the time when Cuvier seemed to be 

 carrying all before him. But such views do not necessarily 

 touch on the question of the mode by which different kinds 

 of animals have made their appearance, though they must 

 naturally lead in the long run to the raising of that question. 

 Nowadays it may be said that naturalists generally have 

 yielded to the doctrine which was most distinctly elaborated 

 at first by Lamarck, that the assumption of the immutability 

 of species was a mistake. In the early part of the century 

 Lamarck and Geofifroy St. Hilaire got thus far, but it was not 

 till Darwin wrote that it was generally recognised that the 

 doctrine of immutability had been accepted on grounds 

 other than scientific, and that there was a great body of 

 evidence in favour of common ancestry of forms widely 

 separate. It has flowed from this change of view that the 

 degrees of genetic relationship or possible consanguinity of 

 distant forms of life are sought for and taken into account in 

 classification. 



I do not think that consanguinity can be actually proved 

 between animals far asunder, but willingly grant that 

 it has overwhelming probability in its favour, provided 

 always it is understood that Natural Selection has nothing- 

 whatever to do wdth Evolution, and that to produce any 

 single step of elevation in the scale of animality, there is 

 something necessary of an inherent and not an environing 

 description, something acting not only in the life of indi- 

 vidual organisms, but on the totality of animal existence 

 from the commencement till now — a something much more 

 akin to the Mathesis of Oken than to Natural Selection. 

 Evolution in organic nature is ever an evolution toward a de- 

 terminate goal, not the jiiroduct of " survival of the fittest. 

 The fittest or ablest to survive in the struggle for existence 

 will survive no doubt, but the question is if that principle is 

 sufficient to account for evolution. Is it a main factor, if factor 

 at all, in evolution as distinguished from variation ? Confining 

 ourselves to the Vertebrata, can it be worked so as to throw 

 the smallest light on the ancestry of a mammal from a primi- 

 tive fish ov the ancestrv of man from any other kind of mam- 



