No. 4.] FUNGOUS DISEASES. 83 



marked the application of preventive measures suggested by 

 the vegetable pathologist. Slowly, however, the latter is 

 gaining recognition from practical men. He is no longer 

 regarded as altogether an airy theorist, or, in the common 

 parlance, a mere "book-farmer;" and, on the other hand, 

 he is gaining consideration as something more than a " plant 

 doctor" or " bug man." Even the less intelligent and pro- 

 gressive farmer is learning that, in order to grow a sound 

 and healthy crop of fruit, some attention must be paid to the 

 needs of the trees in the way of abundant nutriment, a healthy 

 environment and constant tillage ; that, even if these con- 

 ditions are fulfilled, he must guard against the attacks of 

 insects which may ruin his fruit or otherwise curtail his 

 profits ; and, finally, that he must take measures to prevent 

 a host of ills formerly attributed to the weather, to "hard 

 luck," or the over-rulings of a hostile Providence, when, 

 as a matter of fact, in nine cases out often, they are caused 

 by parasitic fungi over which he may exercise a fair measure 

 of control. The vegetable pathologist, then, has to deal 

 with two main causes of plant-disease ; the one due to defec- 

 tive methods of cultivation ; the other, to parasitic attacks 

 on the part of either insects or fungi, or both. 



It is to the last-named topic, the fungous diseases of plants, 

 that I desire to call your attention particularly. I am fully 

 aware that to many of you this is a familiar topic. But, in- 

 asmuch as it is to those to whom it is unfamiliar that I desire, 

 if possible, to make my subject clear, I may perhaps be par- 

 doned for considering somewhat at length the nature of those 

 lowly organisms which we call fungi. 



At the outset let me say that a fungus is as truly a i)lant 

 as is an elm tree. It is not an animal or an insect ; it is not 

 the spontaneous product of wet weather. Like the higher 

 plants, it absorbs nutriment, it grows under favorable condi- 

 tions of warmth and moisture, it reproduces itself by bodies 

 analogous to seeds or by vegetative portions analogous to cut- 

 tings. But a fungus difiers from a higher plant in several 

 particulars. Usually it is very small, often of microscopic 

 size ; its organization is less complex ; it has no true root, 

 stem or leaves. Above all, it produces no true seeds and it 

 possesses none of the green coloring matter distinctive of 



