30 ILLINOIS ACADEMY OF SCIENCE. 



not remain constant if left freely to nature. This was a labori- 

 ous, but profitable method of plant-breeding, the method known 

 in general as mass culture. The most desirable individuals were 

 selected and guarded through a series of generations, until the 

 desired character was built up sufficiently for commercial pur- 

 poses. This is the oldest and still the most widely used method 

 of practical plant-breeding, begun by unconscious selection and 

 merging into intelligent selection. Its limitations are the time and 

 continuous care involved, the lack of constancy in inexperienced 

 hands, and the failure to produce new and constant forms. 



In these days of the rapid evolution of the technique of plant- 

 breeding, there is danger of regarding the old method as out- 

 grown and therefore to be discarded. So far as we can see, it will 

 never be outgrown; for general improvement will always be 

 profitable. The newer methods are concerned chiefly with ex- 

 tending the range of our power to secure new forms for im- 

 provement. 



During all this period of plant improvement by mass culture 

 and continuous selection, the so-called science of Botany was cul- 

 tivating a singularly distant field. In short. Botany was not 

 practical, and plant-breeding was not scientific. Therefore, bot- 

 anists on the one hand, and agriculturists, horticulturists, floricul- 

 turists, etc., on the other hand, were as distinct from one another 

 as if they had nothing in common. It so happened that the 

 botanists were dealing with very superficial problems in a scien- 

 tific way, and that the plant-breeders were dealing with the most 

 fundamental problems in an empirical way. 



As in any other practice, plant-breeding developed now and 

 then a very successful practitioner, who made distinct contribu- 

 tions in the form of important results ; but this represented no 

 more of an advance than does the fact that one cook can surpass 

 another cook in the art of making bread. This caution is neces- 

 sary, for the results obtained empirically by skillful plant-breed- 

 ers are too often ascribed to unusual scientific insight. The re- 

 sult is important enough without reading into it what it does not 

 contain. 



What may be called the. second period of plant-breeding was 

 ushered in when organic evolution began to be put upon an ex- 

 perimental basis. Plant-breeding had been practical, but with no 

 scientific basis ; now a new plant-breeding was estabhshed, which 

 was scientific, and with no practical motive. The new motive 



