102 



DISCOMYCETES [ CH - 



about the time of fertilization vegetative filaments begin to grow up (fig. 60 d\ 

 and at last form a loose investment around and among the developing asc, 

 (fig. 59)- 



Fig. 60. Ascodesmis nigricans Van Tiegh. ; a. b. c. d. development of the sexual apparatus'; a. and 

 b. x 1000, c. xnoo, d. x 800 ; e. communication between antheridium and trichogyne, xi3<x>; 

 f .fusion in oogonium, x 1600; g. septate oogonium and ascogenous hypha; antheridium and 

 trichogyne shrivelled, x 1000; h. uninucleate ascus, x noo; /'. sculptured spores in ascus, x 750; 

 after Claussen. 



Pyronema confluens^ occurs on burnt ground or on charred and decayed 

 leaves in woods. Its fruits are pink or salmon-coloured, its mycelium to a 

 great extent superficial, and its sexual apparatus of unusually large size. 

 The latter fact led to an early study of its development. 



It was described by de Bary in 1863, by the brothers Tulasne in 1865 

 and 1866, by van Tieghem in 1884, and by Kihlman in 1885, and a very 

 clear understanding of the morphology of the sexual organs was reached. 

 A swollen, elongated antheridium was recognized and a more or less globular 



1 Pyronema confluem Tul. = P. omphaloides (Bull.) Fuckel. 



