318 THE POPULAR SCIENCE MONTHLY 



and to ply the crop with all the sprays and washes in succession ought 

 not to be regarded as the utmost that science can attempt. There is 

 at the present time hardly any comprehensive study of the morbid 

 physiology of plants comparable with that which has been so greatly 

 developed in application to animals. The nature of the resistance to 

 disease characteristic of so many varieties, and the modes by which it 

 may be ensured, offers a most attractive field for research, but it is one 

 in which the advance must be made by the development of pure science, 

 and those who engage in it must be prepared for a long period of labor 

 without ostensible jjractical results. It has seemed to me that the most 

 likely method of attack is here, as often, an indirect one. We should 

 probably do best if we left the direct and special needs of agriculture for 

 a time out of account, and enlisted the services of pathologists trained 

 in the study of disease as it affects man and animals, a science already 

 developed and far advanced towards success. Such a man, if he were 

 to devote himself to the investigation of the same problems in the case 

 of plants could, I am convinced, make discoveries which would not 

 merely advance the theory of disease-resistance in general very greatly, 

 but would much promote the invention of rational and successful treat- 

 ment. 



As regards the application of genetics to practise, the case is not 

 very different. When I go to the Temple Show or to a great exhibition 

 of live stock, my first feeling is one of admiration and deep humility. 

 Where all is so splendidly done and results so imposing are already at- 

 tained, is it not mere impertinence to suppose that any advice we are 

 able to give is likely to be of value ? 



But as soon as one enters into conversation with breeders, one finds 

 that almost all have before them some ideal to which they have not yet 

 attained, operations to perform that they would fain do with greater 

 ease and certainty, and that as a matter of fact, they are looking to 

 scientific research as a possible source of the greater knowledge which 

 they require. Can we, without presumption, declare that genetic sci- 

 ence is now able to assist these inquirers? In certain selected cases it 

 undoubtedly can — and I will say, moreover, that if the practical men 

 and we students could combine our respective experiences into one 

 head, these cases would already be numerous. On the other hand, it is 

 equally clear that in a great range of examples practise is so far ahead 

 that science can scarcely hope in finite time even to represent what 

 has been done, still less to better the performance. We can not hope to 

 improve the Southdown sheep for its own districts, to take a second 

 off the trotting record, to increase the flavor of the muscat of Alex- 

 andria, or to excel the orange and pink of the rose Juliet. Nothing 

 that we know could have made it easier to produce the Rambler roses, 

 or even to evoke the latest novelties in sweet peas, though it may be 



