Witches Brooms on Trees 



531 



ferred to parasites. Inasmuch as they are all growths from 

 the tree, we can easily infer that some trees will produce them 

 more readily than others, and that no two trees will grow them 

 exactly alike. They are very seldom seen on oaks, ashes, 

 chestnuts, and many others, and are rare on the conifers, the 



A Single Witches' Broom on an Elm. 

 (From an original photograph by Mr. W. Herridge.) 



blackthorn, the hazel, and a great many others. On birches, 

 beeches, &c, they are common. Some excellent illustra- 

 tions of the different forms of these brooms are given by 

 Mr. E. T. Connold, in his valuable work on " British Galls." 

 His figures are taken from the hazel and the birch. 



Mr. Connold mentions and figures one old birch which had 



