Transactions at the Annual Meeting. 99 



the full data are ascertained, will be interesting at least, and may 

 serve to throw light on the causes of this disease. I was in hope 

 to have had some of the facts to present to you, but cannot, 

 through failure of the parties to respond to inquiries made. Is is 

 alleged that discoveries have been recently made, which, some 

 claim, will forever settle the vexed question as to its origin, and 

 thus remove a prolific cause of contention and dispute. Prof. 

 Burrill, of Champaign, Illinois, announces that "the cause of this 

 dreaded disease is a minute organism belonging to a group of the 

 lowest fungi, best known as hacteria." It is perhaps presumptuous 

 to doubt this solution of the vexed question, and wrong to say 

 anything which will serve to prolong the warfare over this "bone 

 of contention," but I would call attention to some points bearing 

 on this subject, in order to have members note more closely the 

 coming season all the conditions attendant upon the cases of 

 blight that may come under their observation. 



There is no doubt but that minute forms of life are found in 

 connection with blight, but the question is, are they the cause, or 

 the result of it? If the cause, their power to produce the given 

 effect should apply to and cover all manifestations of the different 

 forms in which blight is seen. It should be an adequate cause. 

 So far as it is possible to judge from the facts given, it not only 

 fails to apply to all cases of blight, but does not even seem to be 

 a sufficient cause in any case. Take, for instance, the fact that 

 every experiment to inoculate the tree failed, where the virus 

 containing the bacteria was applied to the young bark and the 

 tender leaves, the places of all others where the opportunity of 

 working themselves into the cellular structure of the tree is the 

 most favorable, if it depended alone on the vital force of their 

 own organism. Could they produce the necessary conditions for 

 their development, they would seem to have a good chance for 

 it here, and failure to do it would go to indicate that they were 

 dependent for these conditions on causes outside of themselves. 



Neither does it seem to us a conclusive demonstration that they 

 are the cause of blight because the disease can be communicated 

 to other trees by inoculation. All are familiar with the pungent 

 odor coming from blighted bark and wood, and the black and 



