PSATHYRELLA DISSEMINATA 57 



gill-surfaces. Finally (7), autodigestion does not proceed from 

 below upwards on each gill or involve any part of a gill during the 

 period of spore-discharge. The collapse of the gills and pileus as 

 a whole takes place only when spore-discharge has ceased. Psathy- 

 rella disseminata is therefore not a Coprinus ; and, for the present 

 at least, there is no good reason for changing its generic position 

 from that given to it by Fries. 



Queleti has also transferred Psathyrella impatiens Fr. and 

 PsathyreUa hiascens Fr. to the genus Coprinus and, in respect to 

 the first-named, has been followed by Lange.^ Unfortunately, 

 I have not yet been able to examine these species myself ; but 

 I cannot help feeling that at present there is no justification for 

 regarding them as Coprini. Fries ^ makes the comment that Psathy- 

 rella hiascens, while having the habit of a Coprinus of the Veliformes 

 section, differs greatly from Coprini in its somewhat stiff and dry 

 gills. Dry gills certainly do not suggest a Coprinus. It will be 

 necessary to re-examine the two species here under discussion and 

 to apply to them the seven criteria which have been enumerated 

 above. I am inclined to think that, when this has been done, the 

 view of Fries, rather than that of Quelet or Lange, will be upheld. 



There can be no doubt that some of the smaller Psathyrellae, 

 such as Psathyrella disseminata and P. hiascens, when examined in 

 the field, have a certain resemblance to some of the smaller Coprini ; 

 and Fries, Quelet, Lange, Atkinson,* and others have rightly 

 recognised this fact. These resemblances are : (1) the ephemeral 

 nature of the fruit-bodies, (2) the softness of the pilei, (3) the 

 weakness and hollow structure of the stipe, (4) the extreme reduction 

 of the pileus-flesh, (5) the splitting of the flesh and gills along 

 radial lines so that the pileus becomes furrowed when it expands, 

 (6) the black spores, and (7) the change of colour of the pileus from 

 whitish or yellowish to dingy grey during the ripening of the spores, 

 which can be seen from above owing to the translucency and 

 splitting of the flesh and gills. The field characters in which the 



1 E. Quelet, loc. cit. ^ J. E. Lange, loc. cit.. p. 47. 



^ Elias Friers, Hymenomycetes Europaei, Upsaliae, 1874, p. 314. 



^ G. P. Atkinson {Studies of American Fungi, Mushrooms edible, poisotwus, 

 etc., Ithaca, U.S.A., edition 2, 1901, p. 48) states that the fruit-bodies of Psathyrella 

 disseminata " resemble small specimens of a Coprinus." 



