GENEOLOGICAL. 377 



recapitulation is general, not exact, that there is 

 often a tendency to abbreviation, and that relatively 

 recent adaptations (kainogenetic characters) may 

 disguise the ancient ancestral features (palingenetic 

 characters) ; let us emphasise that the recapitu- 

 lation-idea was not intended as a contribution to the 

 physiology of development, but was merely suggested 

 as a historical interpretation a light from a dis- 

 tance; and let us even acknowledge that more exact 

 knowledge sees differences where more hasty earlier 

 observations saw only resemblances. Yet, after all, 

 there is a good word to be said for the recapitulation 

 idea. 



If we take an individual animal, like the frog, 

 and study its life-history, we cannot but conclude 

 that in a general way and in respect to certain 

 changes in organs, its ontogeny does recapitulate its 

 phylogeny. 



But let us notice two possible fallacies. In sum- 

 ming up the so-called, we think miscalled, " evidences 

 of evolution," it is customary to cite a case like 

 that of the frog's life-history with its fish-like and 

 dipnoan-like stages as part of the " evidence." 

 The frog, in its tadpole and other stages, is sup- 

 posed to oblige the naturalist the evolutionist by 

 climbing up its own genealogical tree; and that it 

 does so is cited as a corroboration of the evolution- 

 idea. But when we come to study the frog's de- 

 velopment in itself, as part of the practical course of 

 embryology, and are puzzled by its circuitousness, 

 we explain (or are tempted to explain) the turns and 

 twists of the ontogeny by saying, that in so doing 

 the larval frog is recapitulating the historical 

 evolution of its race. 



The second fallacy is this, that when we examine 



