CHAPTER VI. THE THALLOPHYTA. 



3 J 9 



discoid, cup-shaped or club-shaped fructification, which may or 

 may not be the result of an antecedent fertilizing process which 

 takes place in the mycelium growing in the substratum. Some 

 of the forms are parasitic, others saprophytic. The group 

 includes the largest and most highly developed members of the 

 Ascomycetes. Here belong the Pezizas or Cup-fungi, common 

 in woods, growing upon leaf-mould and producing a cup-shaped 

 sporocarp ; the Helvellas, including Morchella (see Fig. 528). 

 Helvella, etc., which have large, mostly club-shaped, sporocarps, 

 the hymenium of which is borne either on a smooth or on a 

 reticulately indented surface ; and the Phacideae, which produce 

 small, blackish, disc-like or roundish fructifications on dead 

 leaves of various kinds. 



The fungus parts of most Lichens also belong in this group, 

 but owing to the composite character of these plants they had 

 best be considered separately. 



Fig. 521. 



Fig. 521. — Diagram of longitudinal section of sporo- 

 carp of Peziza. a, hymenium. 



Fig. 522. — Some of the asci in various stages of 

 development, the more mature showing eight oblong 

 ascospores. The slender filaments between the asci are 

 called paraphyses. 



For a fuller illustration of the life 

 history of these plants we may take 

 Peziza confluens. The mycelium grows 

 in soil rich in organic remains, and 

 sends up ascending branches which de- 

 velop numerous archicarps arranged in 

 rosettes. Each archicarp is ellipsoidal * IG - 522 - 



in shape and tipped with a slender, usually curved, process. 

 Into contact with this grows the antheridium, a slender or 

 somewhat club-shaped branch which sprouts from beneath the 

 archicarp. After the fertilization is effected, numerous hyphse 

 are developed around the rosette of archicarps until a mass of 



