270 Transactions British Mycological Society. 



conidiophores are much branched and since the branches come 

 off in a verticillate manner and terminate in clusters of conidia 

 (figs. 31, 33) the fungus is evidently a species of Botrytis. On 

 one of these conidial areas small hemispherical nodules with a 

 rich brown velvety covering appeared (fig. 36). These on being 

 cut showed the characteristic zoning of Daldinia concentrica. 

 One produced ten zones in three weeks and the cut surface 

 examined three weeks later was found to be covered by the 

 conidial form but on being cut again ceased to grow. 



Tulasne describes the presence of conidia on the stromata 

 pre\'ious to the formation of perithecia ; I have examined many 

 specimens while growing and have only come across traces of 

 this except on stroma of exceedingly small diameter, 3 mm. or 

 less; whereas the creamy conidial patches on bark (fig. 35) 

 which appear before or at the same time as the ball-like stromata 

 are quite common on ash logs. 



During the Selby foray this year (1918) both at Byram Park 

 and Garforth patches of conidia were very abundant in close 

 proximity to the sporophores, and also quite apart from them, 

 on the ash logs which lay scattered about so plentifully. 

 ' Although this conidial form is so common, it is not recognised 

 as belonging to the perithecial stroma, nor does it appear to have 

 been recorded as a Botrytis: as already mentioned several 

 investigators have obtained it by infecting culture media with 

 ascospores, and one, Molliard, recognising its systematic position 

 has proposed to call it Nodidisporinm [Botrytis) Tulasnei; but 

 he considered it was unlike any described species, possibly 

 through being grown under artificial cultural conditions. 



The conidia are colourless and measure 6-5-8 x 5-6/t. 



Culture experiments. Large chunks of ash after being sterilised 

 were infected with conidia as were also small chips in tubes ; — 

 some of these chunks were placed out in the open, others were 

 kept in the laboratory. In the laboratory a fluffy mycelium 

 appeared on them which although white at first gradually became 

 black; when after eighteen months these chunks were placed 

 out in the open air on grass in the shade, the black mycelium 

 disappeared and the characteristic \dllose conidial patches 

 appeared ; the cultures which from the start were out in the open 

 within three months produced conidia but no black mycelium : 

 the conidial patches always became brown. Large patches 

 10 sq. cm. or more have appeared every year on these infected 

 blocks but as yet no perithecial stromata have been seen; the 

 blocks are still in a very sound condition unlike the log on which 

 the perithecial sporophores appear which is in an advanced 

 stage of decay. 



The perithecial stroma. As long as the stroma is growing the 



