82 BOARD OF AGRICULTURE. [Pub. Doc. 



FUNGOUS DISEASES. 



BY DR. WM. C. STURGIS, NEW HAVEN, CONN. 



The subject upon which I have been asked to address you 

 is not a new one. For the past fifty years plant-diseases 

 caused by the attacks of parasitic fungi have occupied, in an 

 ever-increasing degree, the time and attention of scientists. 

 The student of vegetable physiology can no longer confine 

 himself to a study of the normal processes of assimilation, 

 growth and reproduction, as exhibited in the world of the 

 higher plants, for he finds that those functions are constantly 

 being disturbed by external agencies, and that among such 

 agencies are to be reckoned a host of lower plants which 

 prey upon the higher, and by their attacks produce a pro- 

 found disturbance of the normal activities. In other words, 

 he is confronted with abnormal conditions, which, by analogy, 

 he rightly calls disease. Thus there has arisen a compara- 

 tively recent demand for specialists, — men of scientific 

 training, thoroughly informed on the subject of the normal 

 structure and life-processes of the higher plants, able to 

 discern the smallest deviation from the normal course of 

 plant-life, and sufficiently conversant with the man^- external 

 agencies which may disturb that course, as to be enabled to 

 diagnose the special case under consideration and to suggest 

 a remedy. 



Such is the modern student of vegetable pathology. He 

 is to the plant-world what the physician is to the animal- 

 world ; and if, as is certainly the case at present, he succeeds 

 in winning less regard for and support in his work, it 

 is largely because the public, and particularly the farmers 

 of the country, have but an inadequate conception of the 

 vast amount of damage caused annually by plant-diseases^, 

 their extraordinary prevalence, and the incalculable benefits 

 to agriculture which have, during the past quarter-century, 



