FISTULINA 387 



Polyporus adustus (Fr.) is suspected of parasitic tendencies, 

 but no definite proof is forthcoming. On the other hand, 

 Dr. von Schrenk has shown that this fungus causes serious 

 injury to logs of the red gum (Liquidambar styradflua) in the 

 United States. The injury he terms ' sap-rot,' on account of 

 the sap-wood being attacked and destroyed. After logs have 

 been sawn to the proper length and left lying on the ground 

 for six months, the sap-wood at the cut ends is often covered 

 with a dense growth of the fungus, the mycelium of which 

 penetrates from six inches to two feet. The infected wood is 

 bleached. At first there is no material disintegration of the 

 wood, but as the fungus advances the wood becomes more or 

 less pulpy and soft. When green, red gum has such a large 

 quantity of water in its trunk that it sinks in water, hence the 

 logs have to remain piled on the banks of streams for six 

 months or even more, until they are light enough to be rafted 

 to the saw-mills. It is during this period that the injury 

 takes place, and when such diseased logs are sawn into 

 boards it is found that one or two feet at each end of a board 

 is worthless. 



Sap-rot may be almost entirely prevented by coating the 

 ends immediately the logs are cut with hot coal-tar creosote. 



Schrenk, H. von, U.S. Dept. Agric., Bureau of Plant In- 

 dustry, Bull. No. 114 (1907). 



FISTULINA (BULL.) 



Pileus soft and fleshy, flesh coloured and streaked, hyme- 

 nium on the under surface, consisting first of warts which 

 gradually develop into tubes which remain distinct from 

 each other. Tubes at first closed, opening at length and 

 having a fringed margin. 



Conidia are produced in cavities of the old pileus. 



Distinguished from the soft, fleshy kinds of Polyporus by 

 the tubes of the hymenium remaining free from each other. 



Beef-steak fungus (Fistulina hepatica. Fiies.). Hartig con- 

 siders this to be a wound-parasite, and certainly it is very 

 common on old living oaks in this country, less frequently 

 on hornbeam and beech. It produces a deep red-brown 

 decomposition in oak wood. 



Pileus roundish, dimidiate or tongue - shaped, either 



