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Report on Botany. 



inches in diameter. They are not unpleasant to the taste 

 and are sometimes eaten by voracious school boys to whom 

 they are known as May apples, and by whom they are 

 often supposed to be the real fruit of the shrub. So com- 

 monly is this production observed that older and more 

 thoughtful minds have wondered and sometimes even asked 

 why it is that no mention is made of it in any of our bota- 

 nies. The idea seems to have been entertained by some 

 that like most other gall-like excrescences, they are of in- 

 sect-origin, but we have never been able to find anything 

 published concerning them. Having therefore somewhat 

 carefully examined them with a view to ascertain their 

 cause for ourselves, we have come to the conclusion that 

 they are fungus-galls, and as such they have been described 

 and the fungus named in the last botanical report made to 

 the Board of Regents of the University. 



A careful dissection of many galls failed to reveal any 

 signs of insects or larvae in them, neither in old and with- 

 ered galls do any apertures or places of exit appear, as they 

 certainly should if any insect had escaped therefrom. Oc- 

 casionally an insect larva may be found concealed in the 

 external cavities of the gall, and sometimes they eat into 

 its pulpy substance from the outside, but these could have 

 nothing to do in producing it. On the other hand there 

 are evidences of a fungoid origin. The galls soon become 

 covered with a white bloom or minute mealiness, which is 

 found by microscopical examination, to be the spores of 

 a fungus. A further investigation shows that from the 

 whole surface of the gall elongated cells protrude upon the 

 apices of which these spores are borne. The mycelium of 

 the fungus was not satisfactorily traced in the substance of 

 the gall, but there can scarcely be a doubt that by skillful 

 manipulation it may be detected, especially in the younger 

 galls. Similar galls occur upon Andromeda ligustrina and 

 on some species of Vaccinium. It is worthy of mention 



