1 8 The Scottish Naturalist. 



were found to be fleshy, and to enclose a pretty large 

 irregular cavity lined with transparent filaments and 

 small warty tubercles. Examination of the dried gall 

 showed no trace of inmates, but from its structure it is 

 probably the work of mites (or of Vibriofies}). It was 

 found on Deeside a few miles from Aberdeen. 



OBSERVATIOlfS ON THE EEOUERENOE OF THE 



EAKEE PUNai. 

 By Rev. JOHN STEVENSON. 



IN an interesting account of the last Annual Meeting of the 

 Woolhope Club at Hereford, Mr. W. G. Smith says, " It 

 was specially remarked how the species which were formerly 

 abundant upon the charcoal heaps were now totally absent, 

 their places being apparently filled by other species. This is 

 remarkably the case in the instance of Agaricus carbonarius^ 

 a species only recently discovered in Britain ; at first very rare, 

 soon everywhere excessively common, and now apparently 

 gone. The same observation holds good with A. davipes^ * 



This observation is worthy of more than mere passing atten- 

 tion on the part of Mycologists. It can scarcely be accounted 

 for by any of the ordinary conditions of soil or influences of 

 climate. Other causes must be sought for in explanation. 

 Given the same conditions of soil, moisture, and temperature, 

 it will be found that the development of species varies so much 

 from season to season, that their appearance or non-appearance 

 can hardly be attributed to these influences alone. They are, 

 at least, not suflicient to account for tlie disappearance of 

 species. If I am asked, "What cause, then, do you assign for 

 this ?" I cannot answer the question ; but it is to be hoped that 

 the extremely interesting researches of Mr. Worthington Smith, 

 on the reproductive processes in Fungi, may yet cast light on this, 

 as on other unsolved problems in Mycology. When once found, 

 most flowering plants may be looked for with certainty in tlie 

 same localities, if they have not suffered extermination, as some 

 of our rare Scottish plants have, at tlie hands of thoughtless 

 students, or of greedy nurserymen. It is not so with the 



* Qardeners' Chronicle, Oct. 7, 1876, 



