THE FUNGUS BODY. 33 



lie on the surface, and part may penetrate that object ; or all 

 of it may be hidden within the substratum.* Tn some of the 

 common piolds (Mucorini), the cobwebby threads lying upon 

 the surface of the substratum constitute the exposed part of 

 the mycelium, while other hyphae penetrate deeper; in 

 others (Penicillium, etc.), the superficial hyphae become so 



Fig. 31.— a section of part of the aerial body of Polyporus. ^ sfi, hyphae running at an 

 angle to the section, cut across ; A", crystals of oxalate of lime. Magnified about 50a 

 diam.— After Vogl. 



interwoven that they may be lifted off the substratum (as 

 from jellies, jams, syrups, etc. ) as a coherent layer. But in 

 most cases, especially when the fungus grows on a solid 

 medium, the hyphae become adherent to it and permeate it 

 so that they cannot be separated from it, even by the most 

 careful dissection. 



* This non-committal term may be used to designate the material upon 

 which the vegetative part of the fungus grows, whether it be a living 

 body, a. dead organism, or organic matter in solid or liquid form. 



