42 



PLANT LIFE. 



face of the object upon which t he fungus lives; or parts of 

 it may be superficial, and part may penetrate that object ; or 

 all of it may be hidden within the substratum.* In some of 

 the common molds (Mucorini), the cobwebby threads lying 

 upon the surface of the substratum constitute the exposed 

 part of the mycelium, while other hyphae penetrate deeper ; 



K 



Fig. 50. — A section of part of the aerial body of Polyporus. s/>, hyphae running at an 

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

 500 diam. Attn Vogl. 



in others (Penicillium, etc.), the superficial hypha? become 

 so 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. 



