58 RESEARCHES ON FUNGI 



smaller and hitherto doubtful Psathyrellae differ from the smaller 

 Coprini are as follows : (1) the gills do not undergo autodigestion 

 from below upwards during the period of spore-discharge even in 

 the slightest degree, so that they never have inky margins, (2) the 

 pilei remain campanulate or conical during the discharge of the 

 spores, and never finally become flat-topped with recurved margins 

 in the manner characteristic of small Coprini toward the end of the 

 spore-discharge period. In association with the final campanulate 

 or conical form of the pileus it is to be noted that, for Psaihyrella 

 disseminata at least, (3) the gills remain adnate and do not become 

 free from the stipe. In the smaller Coprini, the opening out of the 

 pileus in its later stages is always accompanied by a distinct 

 separation of the gills from the stipe. 



Granted that Psathyrella disseminata is not a Coprinus, one may 

 still ask : is not this fungus closely related to the smaller Coprini ? 

 It seems to me that the answer to this question must be in the 

 affirmative. Psathyrella disseminata and the smaller Coprini, e.g. 

 Coprinus ephemerus, etc., not only possess in common the seven 

 field characters which have been enumerated above, but also a 

 number of microscopic characters which concern the hymenium and 

 the surface of the pileus. Both have : (1) a continuous system of 

 large laterally-united paraphyses which form the ground-work of 

 the hymenium in which the basidia are embedded, (2) a reduction 

 of the generations of basidia to a very small number (in most Coprini 

 this number is two but in Coprinus micaceus it is the same as in 

 Psathyrella disseminata, namely, fovir), (3) polymorphism of the 

 basidia so that each generation has its characteristic length with the 

 result that there is differential protuberancy (in most Coprini the 

 basidia are of two lengths only but Coprinus micaceus and Psathy- 

 rella disseminata agree in having basidia of four different lengths), 

 (4) a close resemblance in the construction of the mosaic-work of 

 which the hymenium is composed in respect to the crowding and 

 relative distribution of the different kinds of basidia and the para- 

 physes, (5) oval or rounded cells which constitute the exterior firm 

 layer of the pileus, some of which are produced from swollen bases 

 into long, unicellular, cylindrical or somewhat conical hairs which 

 under moist conditions excrete drops of slime at their tips (the 



