Daldinia concentrica, J. S. Bayliss Elliott. 269 



ON THE FORMATION OF CONIDIA AND THE 

 GROWTH OF THE STROMA OF DALDINIA 

 CONCENTRICA. 



By Jessie S. Bayliss Elliott, D.Sc {Binn.), B.Sc. {Loud.). 



The curious charcoal-like sporosphore of Daldinia concentrica 

 have often attracted the attention of mycologists and several 

 have kept it under observation for more or less lengthy periods 

 and have also cultivated it and noted points of interest in its 

 life history. In 1863 Tulasne* published an excellent description 

 of the ascophore also noting the presence of conidia on it 

 previous to the formation of perithecia. In 1901 Mollerf pub- 

 lished the results of his observations on the rapidity of growth 

 of the stroma and the duration of spore production. He also 

 germinated ascospores and obtained the conidial condition in 

 his cultures. In 1904 Molliard| published a paper describing 

 how he had obtained the conidial form by sowing ascospores on 

 pieces of carrot enclosed in tubes. Again, in 1913, Brooks§ in a 

 paper describing some culture experiments he had carried out 

 refers to finding conidia on blocks of ash which he had infected 

 with ascospores. Descriptions of the ascophore are also given 

 by Rabenhorst||, Berkeley, Cooke and others. 



For more than five years I have had under observation logs 

 of ash on which both the conidial and perithecial forms of this 

 fungus appeared from time to time. The conidial form was to 

 be seen during the spring, summer and autumn months as a 

 cream-coloured incrustation (figs. 35, 36) several sq. centimeters 

 in area both on the bark and on the sawn ends of the logs, 

 chiefly in the damper parts where they touched the ground and 

 in parts shaded by grass : its surface had a coarsely villose ap- 

 pearance (fig. 36) owing to the tendency of the conidiophores to 

 mass together and form small stromata about 3 or 4 mm. higli 

 by I '5 mm. broad (fig. 36). Colourless conidia were produced in 

 great quantities giving the patches a powdery appearance ; the 



* Tulasne. Selecta fungorum Carpologia, T. ii. 



f Moller, A. Phycomycetes and Ascomycetes. In Schiniper, A. F. W., Bot. 

 Mitth. aus den Tropen, Heft 9. Jena, 1901. 



% MoUiard Marin Forme conidiennede Daldinia concentrica. Bull. Soc. Myc. 

 de France. Tome xx, 1904, pp. 55-60. 



§ Brooks. Observations on pure cultures of some Ascomycetes and Basidio- 

 mycetes. Trans. British Mycological Society, 1913. 



II Rabenhorst. Kryptogam. Flora. Band i, Abth. 2. 



