20 Massee : The Modern Method of Studying Agarics. 



indicated by Fries under these colour-g-roups have been raised 

 to the dig-nity of g"enera. This state of thing-s was certainly 

 not intended by Fries, whose sub-genera of Agaricus as 

 contained in all his works previous to his last popular book — 

 Hymenomycetes Europaei — were composed of members included 

 respectively in each of his artificial colour-groups. 



Modern methods of research, unknown to Fries, prove that 

 o\\ broad lines his conceptions of generic affinity were correct, 

 and that the modern genera included under sections founded on 

 the colour of the spores are artificial, and as stated above only 

 represent portions of true genera, representatives of which are 

 not unfrequently scattered throughout all the colour-groups of 

 the old genus Agaricus. 



The g"eneric characters employed by Fries were the presence 

 or absence of a volva or ring, mode of attachment of the gills 

 to the stem, texture of stem, etc., all naked-eye characters. The 

 modern method, which supplements the macroscopic characters 

 employed by Fries, depends on the microscopic structure of 

 a transverse section of a gill. Numerous experiments have 

 proved that the gill structure is very characteristic and constant 

 for each genus, and tallies in the main with the genera as 

 indicated by Fries, but being more constant than the naked-eye 

 characters, enables a doubtful fungus to be placed in its correct 

 genus when other marks fail to do so. As an example the 

 modern method depending on morphology proves that the 

 modern genera Tricholonia, white spores; Entoloma, pink spores; 

 Hebelonia, brown spores ; and Hypholoma, purple spores, only 

 form collectively one genus. This is only what was shown to 

 be the case by Fries, and evolved from macroscopic characters 

 alone ; yet it is interesting to have this idea corroborated by an 

 entirely different method unknown to Fries. Similar lumpings 

 of other groups of modern genera can also be demonstrated 

 by the same microscopic characters, and was illustrated 

 more satisfactorily by means of diagrams than is possible by 

 writing. 



Finally, I would venture to suggest to the members of the 

 Mycological Section of the Union the desirability of adding a 

 drawing of a transverse section of a gill to every drawing of 

 a fungus made ; preferably the magnification should be 400 

 diameters, the acknowledged standard amongst mycologists. 

 If this were systematically done, we should be able to relegate 

 to their proper genera the numerous species whose proper 

 position is at the present day uncertain or debated. 



Naturalist, 



