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The Museum Gazette 



no fewer than ninety-seven brooms on it. In another instance 

 in which a birch broom had no core, he diligently counted 

 the number of separate twigs springing from the bough and 

 found them more than three hundred and twenty. The 

 twigs which make up a " broom " are of course living, and 

 they bear leaves and shed them just like other parts of the 

 tree. In some instances, indeed, they bear leaves quite as 

 large as the average, but in many the leaves are dwarfed. 

 Brooms do not in any way injure the tree other than that 

 they uselessly consume a certain amount of sap. Whether 

 from insect or fungal irritation they are not infective to the 

 rest of the tree and do not cause decay. 



In the above statements we have, we believe, told the truth 

 respecting the origin and growth of witches' brooms, but by 

 no means the whole truth, and throughout we must ask our 

 readers to understand that we are speaking of " brooms " 

 only, using the word in its popular sense, and not as includ- 

 ing all consequences of insect or fungal irritation on the stems 

 or branches of trees. The latter are a large group, and many 

 of them never assume any broom-like appearance whatever 

 It is probable that what we have stated as to the transitory 

 life of the parasitic cause and the persistency of its results 

 is correct, for in large well-grown brooms it is acknowledged 

 to be very difficult to find any trace of parasite. One able 

 observer, Mr. Roger Williams, came to doubt the existence 

 of a parasitic cause at any stage, on the ground of the entire 

 absence of evidence, and it is probable that many others 

 would agree with him. There are cases, however, in which 

 the permanent presence of a fungus living in the woody 

 structure of a broom and producing its fructification every 

 year, has been proved. One such example of what may 

 almost be considered symbiotic growth, was observed in an 

 example of a broom growing on a silver fir, which was finally 

 cut and brought to the Haslemere Museum. Of this a draw- 

 ing has been preserved. In it the leaves on the branch were 

 all dwarfed. The orange pustules of the fungus were pro- 



