DARWIN AS ECOLOGIST. 



33 



looked for some internal cause for variations, since he maintained that 

 external influences could not produce hereditary results, unless they 

 affected the reproductive system. This may account for the fact that 

 the question of heredity has been so much discussed of late years. 



In plants, all variations in the soma — i.e. the vegetative organs, 

 root, stem, leaves, &c. — arise long before any reproductive organs — 

 i.e. flowers and fruits — exist, since the latter are metamorphosed of 

 leaves. Hence Weismann's view is inapplicable to plants. We 

 now know that, although new adaptations arise in the vegetative 

 system before flowers are borne, nevertheless by some mysterious 

 process the power of forming them is so infused into the whole system 

 of the plant, that they can be reproduced, not only by fragments of 

 the soma, but by the seeds as w^ell; for this power reaches them as 

 being fundamentally part of the soma, too;* perhaps the agent is 

 protoplasmic continuity. 



Conclusion. — It is impossible to say whether Darwin, had he lived 

 till to-day, would have abandoned the theory of Natural Selection as 

 a means of the Origin of Species ; but that his latest views on variations 

 would have been more in evidence in the seventh and later editions of 

 the Origin &c." we may feel quite sure. For example, in 1872 he 

 believed that " changed conditions generally induce mere fluctuating 

 variability, but sometimes they cause direct and definite effects"!; 

 whereas, in 1876 he wrote: "Now there is a large body of evi- 

 dence. ' ' X 



In the Conclusion " Darwin shows how keenly he felt that he 

 had been misrepresented by writers who asserted that he " attributed 

 the modifications of species exclusively to natural selection." He calls 

 the reader's attention to the Introduction of the first edition, in which 

 he wrote: " I am convinced that natural selection has been the maia 

 but not the exclusive means of modification." (1859.) He adds : " This 

 has been of no avail. Great is the power of steady misrepresentation ; 

 but the history of science shows that fortunately this power does not 

 long endure. "§ 



It may be observed that nineteen years had then elapsed since the 

 first edition was published; and the misrepresentation still exists, and 

 forty years have passed since he corrected the last edition in 1872. 



I trust this lecture will go some way towards not only proving 

 Darwin to have been justified in his complaint; but that it will show 

 those who still misrepresent him, that he found abundance of evidence 

 of the origin of species without the aid of any selection at all. 



The Origin of Species hy Means of Natural Selection is, in fact, 

 now quite out of date; for Darwin's faith in the direct action of 

 changed conditions of life, in producing new varieties and species, has 

 been proved by ecology to be based on incontrovertible facts. 



* I have shown many examples in my The Heredity of Acquired Characters 

 in Plants. 



t Origin, <fcc., sixth edition, p. 131 [corrected to 1872]. 



X Life, &c., iii., p. 159. § Origin, <fcc., sixth edition, p. 421. 



VOL. XXXVIII. 



D 



