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are entirely different from all otliers. They do not possess green coloi'ing matter — 

 this fact shows they must feed in an entirely different way from the plants that have 

 green colouring matter. The plants with green colouring matter can take in gases from 

 the atmo8phere,and from them elaborate products for their nourishment ; ortheirroots 

 going down into the soil absorb substances, and from dead inorganic matter work up 

 compounds of a more or less complex nature. The fungi cannot do that. Having no 

 green colouring matter they must depend on something else to make their food, and their 

 food, therefore, consists of what we call organic material — that is, something that has 

 been elaborated by plants before them. Thus, at the very outset we have two classes 

 of the fungi — those that live on what maybe termed dead organic matter, such as the 

 mushrooms, living in soil very rich in manure, and another class that live on living 

 matter — on the organized material in living plants. It is in this class you find the 

 injurious types of fungi that are\ to occupy our attention for the remainder of the 

 time. Por convenience sake, those that live on dead organic matter have been called 

 saprophytes and those that live on living matter parasites. I have thought it would 

 be wise that we should fix our attention on some particular forms of these parasites 

 and not wander over the whole division of the fungi. Consequently, 1 have taken 

 those that affect the grape plant. But do you think for a moment that this after- 

 noon, in half an hour or more, I could discuss the various forms of parasites in plant 

 life that affect the grape ? No ; for they have made out some 104 species of fungi 

 that affect the grape. I have just selected three, so that we might focus our 

 attention upon these and leave the others for future study. The first one is what we 

 call the Downy Mildew, or, technically, the Peronospora Viticola. Those who prefer 

 the long name can adopt it, while those who prefer the simpler can call it the Downy 

 Mildew. Let us look into the life history of that and see what a complicated thing 

 it is. At a certain season of the year — in the summer months — in June 

 or thereabouts, you may notice on the upper side of the leaves of 

 the grape yellowish spots, having a sort of downy, white-like appearance. 

 This is all you can see, but if you should place a thin section of this 

 downy-looking spot under a microscope you then find that you have a beautiful 

 little plant. Everyone of these clusters of wooly-like structure are masses of little 

 plants. That is what is called the peronospora, and it is closely allied with the 

 parasite that causes the potatoe rot, both belonging to the same genus until lately. 

 There is a slight difference in the shape of the spoi'es, so that latterly the potatoe 

 rot is put in another genus (Phytophthora) and is not called the peronospora any 

 longer. Let us look at this diagram before us. The spores fall upon the leaf, 

 germinate and work their way in between the cells, as represented here. Here in 

 this figure are several cells, and here is one of the threads of this obscure plant 

 working in between them. Some of these fungi work into the cells, and others 

 work between. This one works between the cells. Every here and there it throws 

 out little threads. You can call them roots, but we technically call them Hanstoria. 

 These dip into the cells and sap the juices of the plant. It is only a question of time 

 when this parasite that has got into the tissue of the leaves has so exliausted the 

 plant's vitality as to injure its vigour and finally cause its death. Now, after it has 

 permeated between the cells and reached a considerable growth at the little openings 

 that are found in the leaves — the openings we call Stomata — it throws up its fruit 

 bearing branches that you see. This is one of the Stomata. Here coming up are 

 five or six little structures and on these a sort of fruit-like arrangement. That is 

 the fruit-bearing portion of the plant. In the potatoe rot you would only have one 

 stem, while in this Peronospora you have sometimes four and five, and even eight. 

 Let us look at that. It may affect the leaf, or it may affect the green twigs, or it 

 may affect the fruit. Here is some fruit that has been affected. That is drawn and 

 enlarged somewhat from nature. Here you have some of the fruit intact and some 

 that IS affected. Here is what we might have expected if it had not been attacked 

 by this parasite. On the upper branches of this fruit-bearing portion of the plant 

 you see a sort of oval-like structures. These are what we would call the spores 

 They will give rise to plants of that nature very shortly. This little thing here is about 



