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Sunday. I have come here without many of his ideas. However, 

 he has some slides which are to be shown, and perhaps I can 

 tell you something about those, and so add to their interest. 



Before the slides are shown, I want, very briefly, to give a short 

 sketch of the history of this disease. It will be very brief, and 

 of a general nature only. The history of the disease has already 

 been published in quite a number of cases, so I will touch only 

 upon the main points. 



Our attention was first called to this disease, I believe, in the 

 fall of 1904 by Dr. Merkel, of the Bronx Zoological Park, in New 

 York city. He noticed that chestnut trees were dying in greater 

 numbers than seemed to be warranted by any previous knowledge 

 of the dying of chestnuts. He looked the matter carefully over, 

 as I understand it, and decided that there was a definite disease 

 there, and later turned the material over to Dr. Murrill, of the 

 New York Botanical Gardens. Dr. Murrill studied this disease 

 and later published his findings upon it, naming the fungus which 

 caused the trouble, Diaporthe parasitica, a new species of the 

 genus. At that time, I believe, Dr. Murrill stated that it was a 

 very serious disease, and sent out a warning to that effect. If 

 1 am misquoting him, I hope he will correct me, for he is in this 

 room to-day. It was not until 1907, three years after the dis- 

 covery of this disease, that a laboratory was established in Wash- 

 ington for the study of tree diseases. Since that time almost 

 immediately and since then certain investigations, both in the 

 laboratory and in the field, have been carried on in Washington. 

 I do not propose to say anything about these studies at the pres- 

 ent time. My point here is to give you a general idea of the 

 disease, what it looks like, how it affects a tree, and things of 

 that sort, a general discussion of the topic. This review will 

 be, will necessarily have to be, primarily an explanation of the 

 views which will be thrown on the screen. I may elaborate at 

 points, but, as I say, I am not primed as Dr. Metcalf would have 

 been had he been able to be here. I think perhaps we may as well 

 proceed to the views at once. 



Slide No. 1. This, to begin with, shows a diseased spot, as 

 we will find it on the smooth bark of a branch of a chestnut tree, 

 a branch which is perhaps anywhere from three to six inches 

 in diameter. The disease is a fungous disease, and starts its 



