PEZIZALES 



329 



In the Geoglossaceae so far known the antheridia have completely 

 disappeared and, consequently, the ascogonia develop autogamously. 

 They undergo a gradual degeneration : at first they possess a typical form 

 and a well-developed trichogyne, then the typical form is lost, along with 

 the trichogyne, and finally they are no longer formed and the develop- 

 ment of the ascogenous hyphae takes place pseudogamously. 



In contrast to the previous families, imperfect forms are still unknown 

 in the Geoglossaceae on account of their saprophytism on decaying wood, 

 etc. ; in Spathularia and Cudonia it has been noted that the ascospores 



Fig. 218. — Spathularia velutipes. 1. Ascogonium with ascogenous hyphae. Rhizina 

 undulata 2. Young ascogonium. 3. Development of ascogenous hyphae. (1 X 1,330; 

 2, 3 X 335; after Duff, 1922, and Fitzpatrick, 1918.) 



(as also in the Dermateaceae in Tympanis and in the Patellariaceae in 

 Biatorella) may germinate to a sprout mycelium while still in the ascus. 



In summary, the Inoperculatae are an entirely indefinite mixture of 

 various poorly known genera which will only be arranged in clearer 

 lines after more detailed ontogenetic investigations. Apparently the 

 lower forms connect directly to the Plectactascales and Myriangiales 

 and perhaps properly belong there. As long as their ontogeny is 

 unknown, however, an approach to the understanding of the Inopercu- 

 latae and the Discomycetes in general is closed to us. 



On the other hand, we are comparatively well informed on the onto- 

 genetic relationships of the Operculatae, in any case in the lower forms. 

 They are here described for only the five more important families, the 

 Rhizinaceae, Pyronemaceae, Ascobolaceae, Pezizaceae and Helvellaceae. 



