REVIEW OF FUNGOUS CLASSIFICATION 623 



As a consequence of this numerical increase, the asci of the Euasco- 

 mycetes gradually acquire the significance of new integral forms of 

 fructification, which finally become so predominant that they are called 

 the perfect forms. The life cycle of the Euascomycetes, consequently, 

 divides into two cycles whose rhythms run parallel or in sequence; into 

 an asexual cycle in the haplont propagating by imperfect forms, conidia, 

 etc., and into a sexual cycle which occurs in the dicaryophase and con- 

 cludes with the perfect form, the asci. In the lower Euascomycetes, 

 e.g., in the lower Plectascales, (p. 166) the asexual cycle predominates; 

 in the highest Euascomycetes, e.g., in the Helvellaceae (p. 346) and the 

 Tuberales (p. 354), the sexual cycle predominates. Between these 

 groups in which both rhythms have developed equally and lead to fructi- 

 fications standing morphologically at the same height, as the Nectriaceae, 

 Tubercularia, fructification of imperfect form; Nectria stromata, fructi- 

 fication of perfect form (p. 236) ; the Polystigma group, pycnia, fructifica- 

 tion of imperfect form, perithecia, fructifications of perfect form (p. 229) 

 and the Cordyceps group, Isaria, fructification of imperfect form, Cordy- 

 ceps stromata, fructifications of perfect forms (p. 253). 



Differing from this rapid ascent of the Euascomycetes in regard to 

 their fructification, especially those of the perfect form, they show 

 astonishing identity of sexual organs. Even in the lowest forms the 

 archicarps undergo a further differentiation into a receptive organ, the 

 trichogyne, and the true functional part the ascogonium (Monascus- 

 Pyronema type), both of which types are subsequently repeatedly septate 

 and coil; this development, however, is notably limited to the female 

 gametangia as in the fungi altogether only these (as their various names, 

 oogonium, ascogonium, scolecite, etc., indicate) have undergone a further 

 morphological development. For the rest the condition caused by this 

 functional differentiation is retained in entire uniformity throughout all 

 twelve orders of the Euascomycetes as, to cite a few of the more important 

 forms studied cytologically, the Gymnoascus-Monascus-Magnusia group 

 of the Plectascales (p. 166) and the Erysiphe-Sphaerotheca-Phyllactinia- 

 Lanomyces group of the Perisporiales (p. 192), in Claviceps purpurea 

 of the Hypocreales (p. 248), Venturia inaequalis of the Sphaeriales (p. 

 269), Stigmatea Robertiani of the Hemisphaeriales (p. 298), Cryptomyces 

 Pteridis of the Phacidiales (p. 308) and in the Pezizales, in Pyronema 

 confluens, Ascodesmis nigricans, Ascobolus vinosus, Lasiobolus brachyascus 

 etc. (p. 332). 



Besides this apparent constancy may be noted a peculiar degeneration 

 of sexuality which first appears in a functional degeneration of the anthe- 

 ridium. In some forms, as in the Pyronema confluens- Ascodesmis 

 nigricans group (pp. 332-336), they have become entirely facultative 

 and dependent on nutritive conditions; in other forms, as Lachnea 

 stercorea (p. 343), they still fuse with the ascogonia but nuclear migration 



