ON THE PEAR 



This germ has close cousinship with the vari- 

 ous tribes of bacilli that cause the contagious 

 human maladies. And there is a curious resem- 

 blance between the assault of the microbes on the 

 pear tree and the corresponding assaults of cer- 

 tain bacilli, for example the diphtheria bacillus, 

 on the human organism. In one case as in the 

 other, the bacilli, once they find a lodging place, 

 multiply inordinately and give out excretions that 

 are virulently poisonous. Located on the flowers 

 and fruit of the pear, or finding their way to the 

 inner bark or cambium layer of the tree, they 

 multiply prodigiously and exert a malignant in- 

 fluence that withers blossoms, blights the fruit, 

 and causes the leaves to take on a bronzed red 

 hue that is often premonitory of the death of the 

 tree. 



If they find lodgment in the cambium layer of 

 the trunk, they may spread rapidly in every di- 

 rection, until they girdle the tree, shutting off its 

 supply of sap as effectively as if it had been 

 girdled with an axe. 



Wherever lodged, the colonies of bacilli may 

 be located by the oozing out of k milky or dirty 

 brown sticky liquid when the spring rains come. 

 This liquid is attractive to insects, and as the feet 

 and bodies of these marauders become covered 

 with the germ-laden fluid, the 1 transfer of the 



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