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Report on Botany. 



that the black knots of both plum and cherry trees are 

 produced by the same species of fungus, viz. : Sphceria 

 morbosa, Schw., and that it can and does spread from cherry 

 to plum trees' and from plum to cherry trees, and therefore 

 that there is no safety for some cherry trees in the vicinity 

 of affected plum trees nor for some plum trees in the vicinity 

 of affected cherry trees. We admit that there are certain 

 species both of cherry and of plum trees that do not seem 

 to be liable to the attacks of this fungus, which perhaps is 

 the origin of the theory of distinct species of black knot. 

 Having thus briefly noticed the prominent features in the 

 discussion of this question and added our own observations 

 and conclusions, we dismiss the subject, hoping that ere 

 long we shall be prepared to combat this foe to our fruit 

 in a judicious and successful manner. 



