REVIEW OF FUNGOUS CLASSIFICATION 625 



spores, so that the sporangiophores became conidiophores, these male 

 akinetes would have also developed to exospores and the male gametangia 

 would then have become gametophores (in the Pezizales, Laboulbeniales, 

 etc.). As plausible as this theory is, it breaks down from the entire 

 absence of the hypothetic intermediate members. It is further difficult 

 to explain why some male gametangia would have undergone such 

 entirely different developments than other male and female gametangia. 

 In the second group mentioned above, which leads to autogamy, a 

 parthenogamous sexual act first appears in the place of organic cross 

 fertilization between two or more cells in the ascogonium; the septa are 

 dissolved, the nuclei pair and migrate out into the ascogenous hyphae; 

 to this parthenogamous type belong Poly stigma rubrum (p. 229) in the 

 Hypocreales, Systremma Ulmi (p. 291) in the Dothideales, Rhytisma 

 acerinum (p. 312) of the Phacidiales, the Leotia-Spathularia group (p. 

 327) of the Geoglossaceae, Rhizina undulata of the Rhizinaceae, the 

 Ascobolus citrinus-Ascophanus carneus group (p. 341) of the Ascobolaceae, 

 the Lachnea scutella-L. abundans group of the Pezizaceae and the Laboul- 

 benia chaetophora-Laboulbenia Gyrinidarum group of the Laboulbeniales. 

 Thus the parthenogamous cell fusion is replaced by an autogamous 

 nuclear pairing in the interior of one or more cells of the ascogonium, as 

 in the Ascophanus ochraceus-Saccobolus violascens group of the Ascobola- 

 ceae (p. 342) and Humaria granulata of the Pezizaceae (p. 344). Hand 

 in hand with all these functional degenerations, the archicarps lose their 

 specific form, trichogyne, etc., and morphologically appear increasingly 

 like the vegetative hyphae, as in the Leotia-Spathularia series of the 

 Geoglossaceae, in Lachnea abundans and Humaria rutilans of the Pezizaceae 

 and in the Icmadophila-Baeomyces series of the Discomycetous lichens. 

 And, finally, this detour around the reduced female sexual organs disap- 

 pears and the sexual acts no longer occur in special organs, but between 

 ordinary vegetative hyphae, so that the ascogenous hyphae arise directly 

 from vegetative hyphae rich in reserves, e.g., in Trichoglossum hirsutum 

 (p. 327) of the Geoglossaceae, Humaria rutilans of the Pezizaceae and 

 Baeomyces roseus of the Discomycetous lichens. 



Thus it is characteristic in the sexuality of the Euascomycetes that 

 always different substitutes for the sexual act occur. If already in 

 the Phycomycetes the gametangia replaced gametes, so in the Euasco- 

 mycetes the male gametangia disappear, and the sexual act occurs between 

 female gametangia and imperfect forms or in the interior of the female 

 gametangia, between two or more sexual cells or in the interior of a 

 single sexual cell, by simple nuclear pairing or, after the female game- 

 tangia have degenerated, without sexual organs between any two vege- 

 tative hyphae. 



In both these partial processes, which together constitute copulation, 

 plasmogamy and caryogamy, a shifting then a degeneration occurred. 



