CLASSIFICATION 355 



Strobilomyces 

 The one British species inchided in this genus is somewhat rare 

 and local in its distribution. The general structure is that of 

 Boletus, differing mainly in the coarsely scaly cap, and globose 

 spores. 



FiSTULINA 



The one British species is known as the " beef-steak fungus," 

 on account of the appearance of the thick, succulent flesh of the 

 cap when seen in section. The fungus growls horizontally, and 

 forms large, flatfish, thick flaps, sometimes weighing several 

 pounds, and somewhat resembles a large flap of raw liver in appear- 

 ance. Edible, but toughish. Almost confined to old oak trunks 

 in this country. 



POLYPORUS 



Cap fleshy, tough, rather soft when growing ; stem central, lateral, 

 or absent. Some of the species are very large, forming dense tufts 

 at the base of stumps and on trunks. Cap never concentrically 

 grooved nor zoned. Pores never stratified, that is, consisting of 

 more than one layer. 



FOMES 



Cap thick, hard and woody, often covered by a very hard cuticle 

 or crust, usually concentrically grooved, never scaly nor velvety, 

 smooth, usually brownish in colour, sessile with one exception, 

 Fomes lucidus, which usually has a distinct lateral stem, that 

 varies much in length. Tubes stratose, or composed of two or 

 more superposed layers, which are sharply defined by a line, easily 

 seen when a section of tlie hymenium is examined. 



Several are injurious parasites on forest and fruit trees. 



POLYSTICTUS 



Cap quite thin and pliant, silky or velvety, and usually marked 

 with coloured concentric zones, sessile, growing horizontally, and 

 usually attached by a some\\'hat narrowed base. Tubes very short, 

 not stratose. 



PORIA 



This genus includes a considerable assemblage of species, all of 

 which form thin crusts on wood, twigs, etc., being attached by the 

 entire under surface, the upper or free surface being covered by 

 the porous hymenium. Some are probably only depauperized 

 conditions of Polystictus or Polyporus. 



Trametes 

 A genus somewhat difficult to define. It resembles Polyporus or 

 Fomes in general appearance, but differs in the tubes not all ending 

 exactly at the same level where they join the flesh of the cap, but 



