INTRODUCTION xxxi 



prosperity, and is apt to be soon checked by the severe 

 laws of life. To the gardener, however, it often seems 

 an excess to be encouraged, and he encourages it by 

 selection on a different principle from that of nature. 

 He may also encourage an increase in the size of the 

 flowers and a greater brightness or variety in their 

 colour by the same means. Such changes or improve- 

 ments have been practised from time immemorial, 

 particularly in the East, so that the origin of some 

 garden flowers, as, for instance, of several kinds of 

 roses, is unknown to us. In the seventeenth century 

 there was a great variety of florists' flowers, and partic- 

 ularly of carnations, as we can tell from the illustra- 

 tions to Parkinson's Paradisus. The Dutchmen had 

 then developed Tulips and Hyacinths and Crocuses 

 pretty much as we have them now; and most of 

 them were far removed from the original natural 

 species. But all these developments were produced 

 by simple selection and cultivation. The principles 

 of hybridization were not understood, and the process 

 therefore could not be practised artificially. Now 

 that these principles are understood and can be prac- 

 tised, however empirically and imperfectly, our florists 

 have an enormous advantage over their forefathers; 

 and as their knowledge increases of the conditions 

 most favourable to hybridization, that advantage will 

 grow still greater. Already changes are being worked 

 upon certain plants with wonderful speed. The Piansy, 

 as we have it now, has been developed out of the little 

 wild Pansy (Viola tricolor). The process began about 



