394 BRITISH FUNGI 



POROTHELIUM 



Forming thin, entirely adnate crusts on wood and bark. The 

 surface is entirely covered with minute granules, which become 

 perforated or dimpled at the apex. 



Phlebia 



Entirely adnate or with the edge more or less free and project- 

 ing from the matrix, often rather soft and subgelatinous, the sur- 

 face covered from the first with crowded, irregular, small wrinkles 

 or ridges that have usually an entire edge, and often have a ten- 

 dency to radiate on all sides from the centre towards the edge. 

 Liable to be confounded with some of the simple, resupinate species 

 of Merulius, but in Phlebia the ridges do not anastomose, or run 

 into each irregularly, to form shallow pores or pits, as they do in 

 Merulius. 



Hydnum 



The most perfect species have a cap and a central stem, hymenium 

 on the under surface ; the simplest forms are entirely resupinate 

 with the hymenium uppermost ; hymenium covered with pointed 

 spines free from each other at the base. 



This genus requires to be carefully distinguished from Irpex, its 

 closest ally. In Hydnum the spines spring from a flat base ; whereas 

 in Irpex the spines spring from more or less raised ridges or wrinkles 

 present on the hymenium. 



I. Stem present, central or nearly so. 



H. imbricatum. — Cap 3-4 in. across, dusky, with overlapping 

 scales ; stem 1-3 in. long, stout, of equal thickness ; spines pale 

 grey, i-| in. long. 



Known by the scaly cap and stout stem. 



On the ground in pine woods. 



H. squamosum. — Cap smooth at first, then irregularly scaly ; 

 stem short, white, narrowed below ; spines greyish brown. 



Differs from H. imbricatum in the white stem tapering downwards. 



On the ground in pine woods. 



H. scabrosum. — Cap very fleshy, top-shaped, then fiat, rusty 

 umber, downy, then becoming broken up into squamules, 3-4 

 in. across ; stem stout, grey, blackish below ; spines crowded, 

 brownish. 



On the ground amongst pines. 



H. Icevigatum. — Cap smooth, dusky, 4-7 in. across ; stem pale 

 brown ; spines pale brown, crowded, thin, about \ in. long. 



On the ground in pine woods. 



H. fragile. — Cap fragile, edge wavy or lohed, pale, then grey or 

 often brick-red, almost smooth, 4-7 in. across, often zoned ; stem 

 smooth, greyish, stout ; spines i-| in. long, whitish, then grey. 



