2o8 PLANT DISEASES 



and the curved stem three to six inches long ; the colour 

 of every part is clear yellow. The cap is covered with a 

 glutinous liquid, and like the stem is ornamented with 

 rust-coloured scales arranged in irregular circles; these 

 scales, along with the glutinous substance, are usually 

 washed off by rain as the fungus becomes old. The gills 

 are at first pale yellow, then rusty orange. 



This fungus is not uncommon as a saprophyte, growing 

 on decaying timber, stumps, trunks, etc. ; but Tubeuf has 

 shown that not unfrequently it becomes a wound-parasite, 

 growing on living trunks of silver fir, beech, plum, etc. 

 The white wood of the fir becomes yellow or hone)'- 

 colour with scattered patches of light brown, and eventu- 

 ally breaks up into irregular pieces under the influence of 

 the mycelium of the fungus. 



Preventive Means. — The only known mode of repro- 

 duction of the fungus is by means of spores ; hence all 

 fungi should be collected and either burned or buried. 

 Protect all wounds by applying a coat of tar. 



The following Agarics also sometimes grow on living 

 trees : — 



Pholiota aurivella (Batsch) resembles PhoHota adiposa 

 (Fries) in general appearance, but the stem is always dry, 

 not sticky. Often solitary. 



Pholiota squarrosa (MiilL), densely tufted, dry, yellowish- 

 brown ; pileus and stem, up to the ring, ornamented with 

 projecting brown scales. Smell strong. 



Pholiota destruens (Brond.). — Pileus dingy white or 

 yellowish, floccosely squamulose; stem whitish, squamu- 

 lose. On poplars. 



