394 



RESEARCHES ON FUNGI 



fruit-bodies, when examined in the dark-room, give out no light 

 at all, but that after dry fruit-bodies are moistened by holding them 



Fig. 171.^ — A shadow-photograph of a dried frond of Adiantum made with 

 the light given out by the mycehum of Panus stypticus physiological 

 form lumiyxescens of North American origin. The luminescent mycelium 

 was growing down the side of a block of Birch wood contained in a fruit- 

 jar (c/. Fig. 170). The fern leaf was held in a printing frame against the 

 film of a photographic plate, and the frame was set as close to the fruit- 

 jar as possible. Plate developed after 24 hours exposure. Natural size. 



at intervals in a stream of water under a tap their luminescence 

 is very soon regained. 



On several occasions, when my eyes have been in a sensitive 

 condition, I have wetted a dried fruit-body in the dark-room and 



