370 



BOTANY 



Fig. 293. — Cluvaria auro/ii- 

 tiaca. (Nat. size.) 



2. In the group of the ThelepJwreae, distinctive fructifications of a simple type 

 are found. They are composed of closely interwoven hyphse, and form on the 

 trunks of trees either flat, leathery incrustations bearing the hymenium on their 

 smooth upper surfaces ; or the fiat fructifications become raised above the substratum 

 and form bracket-like projections, which frequently show an imbricated arrangement, 

 and bear the hymenium on the under side (e.g. Stereuni hirsutum, common on the 

 stems of deciduous trees). 



3. The fructifications of the Glavarieae are also gymnocarpous, having the 

 hymenium on their upper surfaces. They form erect whitish or yellow -coloured 



bodies, either fleshy and club - shaped or more or less 

 branched, resembling coral (Clavaria, Fig. 293). The larger 

 profusely branched forms of this group are highly esteemed 

 for their edible qualities ; in particular, Clavaria flava, 

 whose fleshy, yellow-coloured fructifications are often ten 

 centimetres high, also Clavaria coralloides and Sparassis 

 crispa, which grows in sandy soil in Pine woods, having 

 fructifications half a metre thick, with compressed leaf-like 

 branches. 



4. The Hydneae have fructifications with spinous pro- 

 jections over which the hymenium extends. In the simpler 

 forms the fructifications have the appearance of incrusta- 

 tions, with spinous outgrowths projecting from the upper 

 surface ; in other cases they have a stalk termed the 

 stipe, bearing an umbrella - like expansion, the pileus, 

 from the under side of which the outgrowths depend. The latter form is exhibited 

 by the edible Fungi Hydnum inibricatum, which has a pileus 15 cm. wide, and 

 Hydnum repandum (Fig. 294), with a yellowish flesh-coloured pileus. 



5. In the Polyporeae the stalked or sessile and bracket-shaped fructifications 

 are indented on the under side with pit-like depressions, or deep winding passages, 

 or covered with a layer of tubes, closely fitted together and lined by the hymenium. 

 To this family belongs the genus Boletus, which has a large, thick-stalked pileus, 

 covered on the under side with a layer of 

 narrow dependent tubes. Although many 

 species of this genus are edible (e.g. B. 

 luteus, B. edulis, B. scaber), others are 

 exceedingly poisonous, in particular B. 

 Satanas (Fig. 295). This latter Fungus 

 has a yellow to reddish-purple stalk, with 

 red reticulate markings above, while the 

 pileus, which may be 20 cm. wide, is yel- 

 lowish-brown on its upper surface, but on 

 the under side is at first blood -red, becom- 

 ing later orange -red. Of the numerous 

 species of the genus Polyporus, P. fomen- 

 tarius, Touch-wood, is officinal (Fungus 

 chirubgokum). Its mycelium is parasitic 

 in deciduous trees, especially the Beech, 

 and produces large, bracket or hoof-shaped 

 perennial fructifications, 30 cm. wide and 15 em. thick. They have a hard, gray 

 external surface, but inside are composed of softer, more loosely woven hyphre, and 

 were formerly used for tinder. The narrow tubes of the hymenium are disposed on 



Fig. 294. — Hydnum repandum. (Reduced.) 



