42 



RESEARCHES ON FUNGI 



Coprinus radians (Fig. 25). ^ This fungus has been observed with 

 its fruit-bodies situated on damp plaster in old houses. We must 

 not assume, however, that the mycelium in such a case feeds and 

 grows at the expense of the plaster. It seems much more reasonable 



Fig. 24. — The lower half of a cellar-wall of a house at Birmingham, England. On 

 the right, some wood-work attacked by Merulius lacrymans, the Dry-Rot 

 Fungus. At A the mycelium is growing outwards over one of the boards and 

 over the bare bricks. Some of the mycelium, via crevices in the mortar, has 

 grown from the wood-work into the wall, has found its way between the two 

 courses of bricks, and has finally emerged at B through a channel, about 2mm. 

 wide, in the mortar of one of the joints. The patch of mycelium at B is 3 feet 

 from the wood-work and is spreading radially over the surface of the wall. 



to suppose that the mj^celium attacks the moist wooden laths 

 beneath the plaster first, and then produces an ozonium which 

 penetrates through crevices in the plaster to the exterior surface, 

 there giving rise to the fruit-bodies. The latter, thus becoming 

 freely exposed on. the exterior surface, are in a position where they 

 can successfully produce and liberate their spores. The advantage 

 of the existence of an ozonium in such a case is self-evident. Upon 



^ Coprinus domesticus was described before C. radians and alone appears in 

 Fries' Sysiema Mycologicum (1821). 



