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Mycologia 



the young white pine is especially susceptible to diseases which 

 may result from the most trivial wound. 



The blight is characterized by the death of the apical portion 

 of the leaf, which may extend over one fourth or one third of its 

 length or entirely to the base, causing premature falling of the 

 leaves. During the early stages of the disease the leaves be- 

 come reddish-brown, but a few months later the color fades so 

 as to be much less conspicuous, which change of color is likely 

 to be mistaken for an improved condition of the trees. 



The leaf-blight is known to extend from the southern part of 

 Maine and northern New Hampshire and Vermont to the Hud- 

 son Valley, central Pennsylvania and along the Alleghanies to 

 western North Carolina, but apparently does not occur in the 

 higher altitudes of the north, as it has not yet been found in the 

 Adirondacks. 



Several species of fungi have been found to accompany the 

 blight, any one or all of which may have to do with its existence. 

 Such physiological factors as winter-killing, sun-scald, injurious 

 gases, etc., may or may not be concerned. The disease may 

 cause the death of the affected trees in a single season or it may 

 require two or more seasons to accomplish its purpose. 



A study of the disease seems to indicate that comparatively 

 few trees have been killed and timber owners have no occasion 

 for undue alarm, as in many cases the trees show a tendency to 

 recover from the blight. There is at present no known reason 

 for cutting healthy trees of young pine among which are scatter- 

 ing trees affected by the leaf-blight. 



Dr. William W. Ford, of the Bacteriological Laboratory of 

 Johns Hopkins University, delivered an address before a special 

 meeting of the Boston Mycological Club, June 14, 1909, on the 

 distribution of poisons in mushrooms, which was printed in Sci- 

 ence for July 23. Dr. Ford has carefully investigated and ex- 

 perimented with a number of species of mushrooms in recent 

 years, and his conclusions, as given in this address, probably 

 represent the most reliable information on this subject at the 

 present time. 



The deadly Amanita phalloides, with its several varieties, was 



