PROCEEDINGS OP THE SUMMER MEETING. 65 



TWO CLASSES OF FUNGI. 



The fungi of our fruits, as is the case with all other forms, may, for our 

 present purpose, be divided into two classes — (1) those that remain for the 

 most part outside the tissues of the plants, and (2) those that are devel- 

 oped within them. These fungi, like other plants, form spores in one or 

 more ways, that act as seeds to perpetuate the species. So soon as they 

 develop they are likely to be moved about in some way, generally by the 

 wind, and if they fall upon plants of the proper kind they will germinate, 

 provided a sufficient amount of moisture is present. As for seeds, the 

 presence of moisture is necessary for germination, and this explains, in 

 part at least, why the various fungous diseases are, as a rule, more 

 injurious in wet than in dry seasons. 



After germinating, the threads of the fungus find access to the interior 

 of the plant, penetrating the cells and absorbing the contents. As a 

 result, the cells shrivel and dry up, giving the portion of the plant involved 

 a brown appearance. After a time the fungus develops spores, generally 

 in great numbers, by which it is propagated and distributed. 



In a general way, it will be seen that there is a very close analogy 

 between the life history of the fungi and that of the higher plants. 



INJURY NOT CONFINED TO ONE SEASON. 



The injury from fungi is several fold, and is by no means confined to 

 the portion of the plant attacked. The stems, leaves, and fruits upon 

 which it appears, are, in severe cases, destroyed outright. The fungus 

 taking up the food designed for other parts of the plant, may thus affect 

 quite distant portions by destroying the leaves. The power of the plant 

 upon which it is feeding, of developing food, is greatly decreased and its 

 growth is thus checked. 



It will thus be seen that the damage is greater than appears at first 

 sight, as not only is the portion where the fungus shows destroyed, but, 

 from one or both of the other causes, growth in other parts of the plant 

 may be nearly or quite prevented. 



HOW FUNGI MAY BE DESTROYED. 



It has been found by experiment that the seeds (spores) of fungi, if 

 brought into contact with certain materials, are unable to develop, and 

 upon this fact the spraying of plants with fungicides depends. While 

 various chemicals have a good effect, there has been nothing found which 

 equals copper sulphate; and the preparation known as Bordeaux mixture 

 is for most purposes preferred to all others. The only objection to it is 

 that it forms a sort of whitewash over the plants, and it is not well to 

 apply it to portions of plants which are to be eaten, within four weeks 

 from the time they are to be used. If properly applied it will disappear by 

 that time and no injurious effects will be produced. 



From the fact that most of the fungi live in the interior of other plants, 

 they are beyond the reach of any treatment after they have obtained a 

 foothold, and our only hope is in preventives. It can readily be seen, 

 from what has been said, that, if the entire surface of a plant can be kept 

 covered with some fungicide during the growing season, the spores which 

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