268 RESEARCHES ON FUNGI 



In 1916, Richard Falck ^ published a paper on the discharge of 

 spores in the Discomycetes in which he pointed out that Morchella 

 escidenta, Gyromitra esculenta, and other Morchellaceae emit clouds 

 of spores when they are warmed by heat radiated from a lamp 

 (Fig. 128), etc. ; and he called the Discomycetes which emit spores 

 when warmed the radiosensitive Discomycetes. ^ He did not investi- 

 gate the shape of the asci in the hy menial chambers of Morchella, 

 etc., and thus failed to observe that they point toward the openings 

 of the chambers. In the belief that the asci are straight and 

 directed perpendicularly to the surface of the hymenium, he ^ said : 

 " In the chambers of the Morchellae the opposing walls are at most 

 1 cm. and, as a rule, only a few mm. from one another ; so that, if 

 no secondary forces came into play, these walls would bespatter 

 one another with spores. Still more unfavourable are the conditions 

 in the narrow and winding passages of Gyromitra." He * placed 

 cover-glasses against the sides of some of the fruit-bodies and 

 noticed that, when clouds of spores were emitted, the spores were 

 deflected from their courses by the cover-glasses as if they were 

 being carried by air-currents. He ^ therefore argued that, when a 

 Morchella or a Gyromitra fruit-body is irradiated by heat from a 

 lamp, etc., air and water- vapour currents {Luft- unci Wasserdampf- 

 stromungen) are produced in the hymenial chambers and passages 

 and these currents bear the spores along and thus enable the spores 

 to escape from the fruit-body. Thus, according to Falck, not only 

 the discharge of the spores but also the escape of the spores from 

 Morchella, Gyromitra. etc., is dependent upon the fruit-bodies being 

 warmed by radiation. 



I am unable to accept Falck's theory of the escape of spores 

 from the fruit-bodies of the Morchellaceae because it is based on 



1 Richard Falck, " Ueber die Sporenverbreitung bei den Ascomyceten. I. Die 

 radiosensiblen Discomyceten," Myrologinche Untersuchungen und Berichfe von R. 

 Falck, Bd. I, Heft II, 1916, pp. 77-144. 



2 In a second paper, " Ueber die Sporenverbreitung bei den Ascomyceten. 

 II. Die taktiosensiblen Discomyceten " {ibiJ., Heft III, 1923, pp. 370-403), Falck 

 treats of spore-discharge in those Discomycetes which puff when touched by a solid 

 object or blown upon ; and he calls such Discomycetes the tactiosensitive 

 Discomycetes. 



3 R. Falck, " I. Die radiosensiblen Discomyceten," lor. cit., p. 133. 

 ' Ibid., p. 133. ■' Ibid., p. 134. 



