200 RESEARCHES ON FUNGI 



sequently of adhering to one another. The significance of the 

 marginal bands with their cystidia seems to be, therefore, that 

 they secure that the faces of adjacent gills, i.e. the hymenial 

 surfaces, shall be suitably spaced during development.^ 



The so-called " deliquescence " of a Coprinus fruit-body has 

 nothing in common with the phenomenon of deliquescence of 

 crystals known to the chemist. The phenomenon with which we 

 have to deal is really a ])rocess of autodigestio7i. The solid parts 

 of the gills become fluid, in all probability through the agency 

 of digestive enzymes. There is not the slightest reason to suppose 

 that the fluid is derived from the water-vapour of the air. 



Autodigestion of a gill always begins at its base, along the 

 free edge where the gill is separating or has just separated from 

 its neighbours (Plate II., Fig. 8, .s). The marginal cystidia are 

 first involved. They simply break down, become fluid and indis- 

 tinguishable. After the destruction of the cystidia, the auto- 

 digestion proceeds obliquely upwards and gradually destroys the 

 whole gill (Plate II., Figs. 8, 9, 10, and 11). The entire destruction 

 of the gills from below upwards in large fruit-bodies was observed 

 to take about two days, whilst in smaller ones the process was 

 carried out in little more than twenty-four hours (<?/. Figs. 69, 

 70, and 71). 



As the gills yet shorter and shorter owint^ to their destruction 

 from below upwards, the pileus gradually opens. It passes from the 

 bell shape to the helmet shape (Plate II., Fig. 9), and at length, 

 as it becomes smaller and smaller, flattens out into a disc like 

 that of a Mushroom (Plate II., Fig. 10 ; Plate IV., Figs. 21 and 22). 

 The remains of the gills thus come to be held out horizontally. 

 In this position they disappear in their entirety, so that merely 

 the naked central flesh of the pileus is left behind (Plate II., Fig. 11). 

 When a fruit-body has completely lost its gills, the stipe often 

 bends in two toAvard the middle, so that the pileus flesh, which has 

 now become very discoloured and ragged, either hangs down or 



^ It might perhaps be shown that the provision of spaces, so that the basidia 

 can develop their spores in air without contact with any obstacle, is a principle of 

 development applying not only to the Coprini, Psalliota, Polyporus, Arc, but to 

 the Basidiomycetes generally. 



