ON VARIATION. 163 



Thus, during 1860 he worked at Drosera, and during 

 the latter part of 1861 and beginning of 1862 at 

 the fertilisation of orchids. In his diary for 1866 

 we meet with the entry, " Nov. 21st Finished ' Pan- 

 genesis/" and later on, "Dec. 22nd Began con- 

 cluding chapter of book." In this year, too, he brought 

 out the fourth edition of the " Origin." When the time 

 for publication approached Darwin was much disap- 

 pointed at the dimensions of the work. It was not 

 published till January 30th, 1868, when it was proved 

 that his fears were groundless, for a second edition of 

 1,250 copies were required in the following month, the 

 1,500 of the first edition having been all absorbed. 



This work is considered by some writers to be the 

 greatest produced by Darwin ; but I think we shall be 

 right in accepting his own opinion that such words 

 should be applied to the "Origin." It is probable, 

 however, that this book stands second in importance 

 in the splendid list of works which have done so 

 much to increase our knowledge of nature and to in- 

 spire others to continue the good work. 



"The Variation of Animals and Plants under 

 Domestication " opens with a very clearly written ac- 

 count of natural selection ; it proceeds to treat of the 

 domestic quadrupeds and birds, describing the differ- 

 ences between the various breeds of each species, 

 and making out as far as possible the history of their 

 development from each other and from the wild stock. 

 Cultivated plants are then treated in the same 

 manner. The first volume concludes with two most 



