EUASCOMYCETES 173 



In Monascus, in contrast to Aphanoascus and the Gymnoascaceae, the 

 female copulation branch no longer fulfils its original sexual function as 

 a whole, but is divided into a receptive cell, the trichogyne, and the true 

 female gametangium, the ascogonium. 



This development continues characteristically in Magnusia, which 

 extends much beyond Monascus both in the imperfect forms and the 

 structure of sexual organs and perithecia. The only representative so 

 far investigated, Magnusia nitida, in contrast to Monascus, has uninu- 

 cleate cells (Satina, 1923). Its imperfect forms are reminiscent of tufts of 

 Penicillium and under favorable nutritive conditions form coremia. 

 The sexual apparatus consists of a unicellular antheridium, a helical 

 ascogonium and a multicellular trichogyne; the latter grows toward the 

 antheridium, embraces it, twines around it, comes into open connection 

 and its content flows into the ascogonium. The latter develops ascoge- 

 nous hyphae according to the hook type. The perithecia are shining black, 

 ellipsoidal or irregularly angular; they have long spiral appendages decep- 

 tively like the appendages of the Erysiphaceae ; only, in contrast to the 

 latter, they do not arise from peripheral but from deeper cells and hence, 

 in a certain sense, are formed endogenously. 



As regards the morphology of the sexual organs, Magnusia is distin- 

 guished from Monascus by the spiral ascogonium, by the septation of the 

 trichogyne and by the length of the latter which varies with the distance 

 from the antheridium. This relationship offers an approach to the com- 

 prehension of several higher orders of Ascomycetes. 



A second line is formed by Thielavia whose best-known representative, 

 T. basicola, appears in damp weather on the roots of numerous phanero- 

 gams and in Europe and North America causes a serious root rot of 

 tobacco. The mycelium penetrates the infected roots in all directions, 

 and on their surfaces cuts off such a great mass of conidia that they seem 

 to be covered by a mildew. Because of their peculiar manner of libera- 

 tion, these conidia are called "endoconidia" by the phytopathologists 

 (Brierly, 1915). A hypha forms a lateral outgrowth and the nucleus 

 divides so that a daughter nucleus migrates into the daughter cell. The 

 daughter cell is abjointed and elongates into a flask-shaped conidiophore 

 (Fig. 108, 1) whose nucleus divides again. One daughter nucleus remains 

 at the base, the other migrates toward the tip which is abjointed. Now 

 the membrane of the terminal cell separates into an outer and inner layer; 

 the outer ruptures at the top and the conidium gradually emerges (Fig. 

 108, 2). Meanwhile the nucleus of the basal cell divides and repeats the 

 ab junction of the conidium. With every conidium, the sheath increases 

 in length and finally a long row of conidia are enclosed in the sheath and 

 slowly press outward. Thus these conidia are not endoconidia in the 

 strict sense of the word, but ordinary acrogenous conidia which, however, 

 have been freed from the mother plant by a peculiar mechanism of libera- 



