CHAPTER XXVI. 



THE EATE OF VARIATION. 



Variation TT is a necessary result of any form of the develop- 

 is s ow . _|_ jjjgjj^ theory, iudeed I may say a part of it, that the 

 process of variation by which any great change in organic 

 forms has been effected has been extremely slow : so slow 

 as to be measurable only by geological time. Darwin 

 constantly insists on this. 



Of course it is impossible to doubt that such a change 

 as that inv^olved in the descent of warm-blooded animals 

 from fishes, or of winged insects from worms, must have 

 occupied immeasurably long geological ages. But Darwin 

 goes much further than this ; he thinks that all species 

 whatever have been formed by a process of variation not 

 more rapid than that by which, in most cases, our domestic 

 but I think races have been, and are, improved. I am inclined here to 

 not so slow (jjg'gj, from Darwin. I think it most likely that, in many 



as JJarwin '> ' ^ •> 



maintains, cases, species have been formed at once by considerable 

 Possible variations ; variations not comparable to that which would 

 origin of be necessary to derive an air-breathing animal from a 

 ^®^. water-breathing one, but amounting to the sudden forma- 



species. . 



tion of new species and new genera. 

 Such has In this belief there is nothing inconsistent with the 

 under l^^ws of life. Variations, equal in magnitude to the pro- 

 doraesti- duction of new species, do occur under domestication. I 



have mentioned, in the chapter on the Laws of Variation, a 

 Poppy. case of a new variety of the poppy appearing suddenly, 



which had "a remarkable variation in its fruit, a crown 

 ^ of secondary capsules being added to the normal central 



tatula. capsule:" and a similar case of the datura tatula, present- 



