ANNIVERSARY ADDRESS OF THE PRESIDENT. CXVU 



viduals naturally produced from parents were modified by successive 

 variations of parts in any stage of early growth or rudimental deve- 

 lopment, until in one or more generations the whole species became 

 in fact a different one ; or whether we are to believe that the whole 

 race perished without reproducing itself, while, independent of it, 

 another new race, or other new individuals (by whatever means) 

 came into existence, of a nature closely allied to the last, and differing 

 often by the slightest shades, yet unconnected with them by descent ; 

 whether there was a propagation of the same principle of vitality 

 (in whatever germ it may be imagined to have been conveyed), or 

 whether a new principle or germ originated independently of any 

 preceding, out of its existing inorganic elements.^' 



In the sentence which I have just quoted, there are two sets of 

 alternatives, and I think that in each set the author has inserted a 

 fallacy in stating the second alternative respecting the theory of im- 

 mutability. In the first set he has assumed, without any warrant, 

 that a whole former race has perished and is succeeded by another of 

 a closely allied nature and often differing only by the slightest shades. 

 In such a case, viz. where the difference is very slight, it may be 

 possible that the second race is really the descendant of that pre- 

 viously existing, slightly modified by the external conditions of life 

 in which it was placed. But the author has omitted all reference to 

 those species which occur in the new or upper formations, whose 

 resemblances or analogies to those of the preceding period are very 

 distant or imperfect, and which cannot therefore be looked upon as 

 the descendants or modifications of the pre-existing forms. There 

 are undoubtedly species which have been continued through many 

 geological periods, have survived many local disturbances, and which, 

 while others may have perished, have been kept alive by greater vital 

 energies or other influences, and have become the associates of new 

 forms introduced for the first time and having no resemblance to or 

 analogy with the forms which had preceded them. We know that 

 some species pass into many varieties, sometimes even contempora- 

 neously with the existence of the typical form ; there is, therefore, 

 surely nothing inconsistent with the theory of immutability in sup- 

 posing, under peculiar circumstances, that varieties of some species 

 may also take the place in a subsequent period of the original typical 

 form. This, however, is the exception, and not the rule. 



With regard to the second set of alternatives in the passage I have 

 quoted, I think Prof. Powell is too much begging the question when 

 he concludes the sentence with these words : *' out of its existing 

 inorganic elements." Surely this is taking too physical or material 

 a view of the matter, and one not required by those principles of in- 

 ductive philosophy which he so strongly supports. The advocates 

 of immutability of species do not generally talk of a principle of 

 vitality originating out of inorganic elements. When old forms die 

 out, and are succeeded by new, the matter of which the new consist 

 is derived from the existing inorganic elements ; but the life or prin- 

 ciple of vitality by which it is animated must proceed from a different 

 source, from that same source, mysterious it may be, which first 



VOL. XII. i 



