ii8 



RESEARCHES ON FUNGI 



clear that, when spore-discharge takes place, the spores must all be 

 shot through the mouths of the alveoU into the open air (Fig. 157, B). 

 Thus, so far as the escape of the spores from a fruit-body of Morchella 



is concerned, we have a direct and very 

 simple explanation, one that is in con- 

 formity with what is known concerning 

 the escape of the spores from the fruit- 

 bodies of simpler Discomycetes, such as 

 species of Ciharia, Aleuria, and Galactinia, 

 and one which, clearly, must take the 

 place of Falck's Temperaturstromungen 

 theory already discussed and criticised 

 in the Introduction to this Chapter. ^ 



The asci on the walls of an alveolus of 

 a Morchella fruit-body all look toward the 

 mouth of the alveolus and toward that 

 part of the mouth from which come the 

 strongest incident rays of hght. There- 

 fore, when pufhng takes place, the spores 

 of any single alveolus are all shot outwards 

 in great numbers in the same general 

 direction. This being so, the same re- 

 sults accrue as those already experiment- 

 ally investigated in connexion with 

 puffing from the cup of Sarcoscypha 

 protracta : the spores discharged from 

 the alveolus strike the air almost simul- 

 taneously, in the same general direction, 

 and very violently ; they set the air in 

 motion ; and they cause an air-current to 

 come into existence sufficiently strong to 

 carry them farther from the fruit-body 

 than they could travel by their own momentum .2 It was mechanically 

 produced air-currents of the kind just described which Falck perceived 

 in his investigations on the discharge of spores in Morchella and its 

 alhes and which he mistook for his " Temperaturstromungen." 

 1 Vide supra, pp. 268-270. ^ yide supra, pp. 257-260. 



Fig 



158. — Morchellci conica. 

 Semi-diagrammatic verti- 

 cal section through the 

 liymeniiim on the upper 

 side of a liorizontal dis- 

 sepiment between two 

 alveoU(c/.einFig. 157, B). 

 The asci, owing to their 

 having responded to the 

 stimulus of liglit, are all 

 curved at their ends to- 

 ward the movitli of the 

 alveolus in which they 

 grew. The arrows indicate 

 the directions in which 

 the sj)ores would be shot. 

 Magnification, 293. 



