BOLBITIUS AND COPRINUS 8i 



discharge which we find in Coprinus does not exist in Bolbitius. In 

 particular, the liquefaction of the gills, which is such an essential 

 feature of the fruit-body mechanism of Coprinus, has nothing to do 

 with spore-discharge in Bolbitius. In Coprinus the autodigestion 

 takes place whilst the pileus is still actively shedding spores, whereas 

 in Bolbitius the turning of the pileus into a brown mucus takes 

 place when spore-discharge has ceased and the whole pileus is 

 exhausted and dead. 



The fruit-body mechanism of Bolbitius resembles in its main 

 features that of a Mushroom. The gills are wedge-shaped in cross- 

 section and are positively geotropic. This ensures that in a normally 

 oriented fruit-body every part of the hymenium looks more or less 

 downwards. Correlated with this fact we find that every small 

 area of the hymenium (every square mm.) produces and liberates 

 spores at one and the same time. On any one small area a series 

 of basidia ripen and shed their spores in succession. 



From the foregoing remarks we may conclude that the arrange- 

 ments for spore-production and spore-liberation in Bolbitius are 

 essentially different from those of Coprinus. 



The hymenium on the sides of the gills of Coprinus consists of : 



(1) Basidia which are dimorphic : long basidia and short are 



interspersed among one another. In a very few species 

 the basidia are either trimorphic or tetramorphic. 



(2) Large and well-developed paraphyses which form a con- 



tinuous system and separate the basidia from one another. 



(3) Large pleurocystidia, present in some species but absent in 



others. 

 The hymenium on the sides of the gills of the Bolbitius 

 consists of : 



(1) Basidia which are monomorphic : the basidia are all of the 



same length and cannot be divided into two sets, long 

 and short. 



(2) Large and well-developed paraphyses which form a con- 



tinuous system and separate the basidia from one another. 



(3) Pleurocystidia are absent or very rare. 



Coprinus and Bolbitius have very similar paraphyses which are 

 remarkable for their high development. On the other hand the 



VOL. III. O 



