136 RESEARCHES ON FUNGI 



fruit-body's requirements. The longer the spore-discharge period, 

 the longer must the fruit-body maintain its hymenial layer in the 

 correct position for the discharge of the spores from the basidia, 

 and the greater the risk from drought, the wind, falling leaves 

 and twigs, the visits of animals, etc. It seems therefore only in 

 accordance with the fitness of things that the longer a fruit-body 

 functions, the more mechanically resistant shall be its structure. 

 The watery consistence of a Coprinus is all that is needed for a 

 fruit-body which, in the expanded condition, is to function for a 

 few hours only or at most for a couple of days. A Coprinus fruit- 

 body with the consistence of a Fomes would be a mechanical 

 absurdity, embodying a waste both of material and of energy. 

 On the other hand, an exceedingly hard and woody frame is just 

 what is required for the perennial fruit-body of a Fomes, which is 

 destined to shed showers of spores from long and narrow hymenial 

 tubes for 5, 10, 20, 40 and, in some instances, for 80 years in 

 succession. During the passage of the years the fruit-bodies of Fomes 

 applanatus, F. igniarius, F. fomentarius, F. officinalis, etc., must 

 withstand the most violent gales of wind, the fall of branches, 

 twigs, and leaves, the pressure of the winter's snow, the pelting 

 of hail-stones, and the visits of birds, squirrels, etc. If they had 

 the watery consistence of a Coprinus, they would be mechanical 

 failures ; for they would not be able to hold their fine tubes in 

 exactly vertical positions for any great length of time, and they 

 would be ruined by external agencies within a few weeks of their 

 appearance. 



In my student days, whilst wandering in an ancient wood near 

 Leipzig, I observed two large fruit-bodies of Fomes igniarius pro- 

 jecting from the bole of an Oak tree, and I was much struck with 

 the discovery that they were so hard and so firmly attached that 

 I was unable to detach them and take them home as specimens. 

 I wondered why they were so rigid and so tightly fixed to their 

 substratum, and whether or not Nature had not been a little over- 

 generous in bestowing upon them the gift of rigidity in so extra- 

 ordinary a degree ; but Nature has now whispered her secret 

 into my ear. It is evident that the rigidity and fixity of all 

 the Fomes species are strictly correlated with the mechanical 



