80 Selection Does Not Lead to Origin of Species. 



duction according to the now current views. ^ They do not 

 arise by chance, they are not the resuh of rare and sudden 

 variations. The material out of which they are made is 

 furnished by fluctuating variabihty. At the outset, the 

 breeder seeks in his fields for those plants which seem 

 the best for his purpose, and collects their seeds sep- 

 arately. These plants differ very little in the eyes of a 

 layman from the other specimens in the field. He sows 

 seeds from these on a small scale, working every year 

 on the same principles, in this w^ay gradually increasing 

 the deviations from the original form in the desired 

 direction. 



He has as a rule one or two qualities chiefly in view, 

 but pays attention where possible to all other characters. 

 He is not concerned with the improvement of one par- 

 ticular quality. To achieve this many things are neces- 

 sary, patience, an intimate acquaintance with the species 

 of plants in question, and a firm and clear conception 

 of the ideal to which he wishes his race to attain. And 

 in spite of the possession of these qualifications the best 

 known breeders are by no means successful with every 

 experiment ; the greatest of them, that is those who have 

 introduced the most widely distributed races, liave often 

 only brought out one or at most a very few successful 

 novelties. 



The value of such a race gradually increases. At 

 first as seed for one's own purpose, but soon as seed for 

 the market. But the seed is not put on the market in a 

 single year but gradually during the period of improve- 

 ment and multiplication. The improved characters de- 



^ For the earlier constant products of selection, e. g., those of 

 Patrick Shirreff, and for my own views concerning the description 

 given in the text see the conckision of § 12, pp. 109 ff. and § 23, pp. 

 178 ff. (Note of 1908.) 



