6 



COMPARATIVE MORPHOLOGY OF FUNGI 



Hum. In the higher forms, a dark, thick, irregularly intertwined rind 

 and a loose, white core are differentiated from parallel hyphae. They 

 serve, as will be shown in the Basidiomycetes, chiefly for transport of food. 



Fig. 3. — Armillaria mellea. Longitudinal section of tip of rhizomorph. a, loose 

 hyphae; b, gelatinous, loosely interwoven hyphal layer; c, d, core layers; e, central cavity; 

 /, apical meristem. ( X 300; after Hartig.) 



Occasionally the conducting function becomes less evident and they 

 attain a more sclerotic character. 



The plectenchyma attains its highest development in fructifications 

 where the differentiation is reminiscent of the cormophytes. 



