NATURAL HISTORY SURVEY 127 



pointed, 6 to 8 mm. long. Pileus 4 to 6 cm. broad; stem 5 to 7.5 

 cm. long, 10 to 14 mm. thick. The species is edible. 



Hydnum adustum Schw. 



Pileus variable in shape, from orbicular and entire to dimidiate 

 and reniform, coriaceous-tough, whitish or pale yellowish. 



Stipe ascending, unequal, central or lateral. 



Spines at first pallid or yellowish, then changing to brown or 

 blackish. Pileus 5 to 7.5 cm. broad; stem 2.5 cm. or more long. 



On dead sticks on the ground, woods, Glencoe. September. 

 Spores elliptic-oblong, 12 to 15 x 6 to 7 /A. Most of the plants 

 were covered with the mycelium of some parasitic fungus. 



Hydnum aurantiacum Alb. & Schw. 



Pileus orange, corky, compact, turbinate-dilated, with small 

 .elevations, zoiieless, often covered with whitish down, zoned 

 internally. 



Stem short, orange. Spines 2 to 4 mm. long, whitish becoming 

 fuscous. 



Pileus 2.5 to 12.5 cm. broad; stem 12 mm. to 5 cm. long, 12 

 mm. to 2.5 cm. thick. 



On the ground in woods. Millers and Glen Ellyn. August. 

 Ht/dnellum flofiforme (Schaeff.) Banker, Mem. Torr. Cl. 12: 159. 



Hydnum zonatum Batsch. 



Ferruginous; pileus equally coriaceous, thin, expanded, some- 

 what infundibuliform, zoned, becoming smooth, radiate-rugose, 

 the paler margin sterile beneath. 



Stem slender, somewhat equal, the base tuberous; spines 

 slender, pallid then ferruginous. 



Sandy woods and borders of swamps, Calumet Heights and 

 Millers. Autumn. Pileus when young or moist, pale wood-color; 

 often confluent; 2.5 to 5, occasionally 7.5 cm. broad; spines be- 

 coming fuscous-ferruginous. Spores pale watery-brown, globose, 

 rough, 4 to 5 ft. 



Hydnum nigrum Fr. 



Pileus azure-blue-black, zoneless, but with a white margin 

 when in fullest vigor, corky-rigid, club-shaped when young, then 

 turbinate, at length flattened, piano-depressed, tubercular, black 

 internally. 



Stem 2.5 cm. long, stout, often rooting, unequal, black, 

 tomentose at the base, internally of the same color. Spines awl- 

 shaped, thin, rather short, white. 



In pine woods, Dune Park, Indiana. October. Pepoon. 

 Hydnum coralloides Scop. 



Pileus much branched, pure white, sometimes becoming yel- 

 lowish with age; branches numerous, spreading, dense, angular 

 or flattened, bearing the numerous awl-shaped teeth along the 

 lower side. 



