8 



SCIENCE 



[N. S. Vol. LIII. No. 1358 



not for scientific or practical purposes, but 

 gave source to wild speculations in disease and 

 th.e origin of life. However, its useful day 

 pame many years later, when its discoveries 

 were made use of in many practical problems, 

 connected with disease of plants and animals 

 and the physiological problems in connection 

 with crop production. 



, PLANT PATHOLOGY 



Meyer, an extraordinary man who died at 

 the age of thirty-six, published a work on 

 phytopathology, a paper on corn smut and one 

 on actinomyces. He was a physiologist and 

 looked at the problem of disease from the 

 standpoint of physiology, really the only way 

 ,the subject should be treated. Camerarius 

 seems to have antedated the work of Meyer by 

 over one hundred years in the publication of 

 his paper " De Ustilagine Frumenti." Julius 

 Kuehn was primarily an agriculturist and as 

 director of the Agricultural Institute at Halle 

 started a series of experiments on plants that 

 have become classic. While thus engaged in 

 ithe work he became interested in a study of 

 the diseases of plants. To him we owe the first 

 pomprehensive treatise on plant pathology. 

 He had breadth of vision to study and inter- 

 pret what he saw with the microscope and thus 

 there came into being "Die Krankheiten der 

 Kulturgewachse," which stands as a monu- 

 pient to his labors. It is the only botanical 

 paper by him listed by Pritzel in his The- 

 saurus. M. J. Berkley's work, " Introduction 

 to Cryptogamic Botany," gave to English- 

 speaking people the first real treatise on plant 

 diseases, which laid a sure foundation for a 

 study of plants, along economic lines. 

 I All of the work on plant diseases and the 

 anatomy of plants was better established later 

 through the classic work of DeBary. De- 

 Bary, of course, did not have, except in some 

 cases, Ifhe practical problems in mind, though 

 the science of botany and plant pathology in 

 particular have been greatly benefited through 

 his profound researches in connection with 

 the development of life history of fungi. De- 

 Bary brought to the science of mycology a 



breadth of knowledge along many lines of bot- 

 any and one marvels at the enormous amount 

 of research work he did. Nor should we omit 

 to mention the great work of Tulasne (who 

 had the merit of first breaking the ground in 

 a study of rust, smuts and ergot), on the dis- 

 covery of the germination of the siwres of 

 rusts, smuts and the sexual organs of Perono- 

 epora. While these researches did much for 

 mycology, indirectly they have been of great 

 practical importance to pathology. Robert 

 Hartig, perhaps the foremost student in the 

 jworld during his lifetime of the diseases of 

 forest trees and the decomposition of wood, 

 exerted a great influence on the practise of 

 forestry, followed later by the splendid work 

 of Marshall Ward, a student of Hartig. We 

 jnay mention in this connection the work of 

 Fischer de Waldheim, Wolff, Sorauer, Appel, 

 MiUardet, Prillieux, Jones, Halsted, Arthur, 

 Bolley, Atkinson, Stewart, Whetzel, Freeman, 

 Clinton, Thaxter, Dxiggar, Stakman, Cook, 

 Stevens and Melhus. These as well as a 

 host of others, added to this economic phase 

 of botany, making secure the science of 

 plant pathology. I need .only add here 

 that the stimulus given by these men to 

 this economic phase of botany has been com- 

 municated to all parts of the world; and 

 so we may mention especially the pioneer 

 work by Dr. Farlow on Gymnosporangium, 

 grape vine mildew, onion smut, Dr. Burrill 

 on apple blight and sorghum blight, the epoch- 

 making researches along the line of bacterial 

 diseases of plants by Dr. Erwin F. Smith. 

 Surely America may well be proud of its 

 achievements. The present age has hundreds 

 of new problems in plant pathology. The 

 superficial only was touched on by the early 

 workers. We may mention especially the root 

 disease of cereals and other crops. The plant 

 pathological studies on these parasites has 

 changed our methods of agriculture com- 

 pletely. We need more careful and profound 

 work on many of the problems worked upon 

 by the pioneers. The pioneers who blazed the 

 way may be excused for errors, but the mod- 

 ern investigator should not be. He has the 



