304 RESEARCHES ON FUNGI 



my hat so as to cast a shadow upon the cups, and I waited and 

 watched for several minutes, but all in vain. Perhaps they had 

 exhausted their ammunition. Away came my hat. The sun again 

 struck the cups. At once two puffs, like a pyrotechnic display ! 

 I tried to measure the height to which the spores had been shot but 

 could only estimate it at 4-6 cm." 



Dr. Giissow's observations show that, under natural conditions, 

 the fruit-bodies of Aleuria vesiculosa not only puff but also shoot 

 up their spores to some distance above the mouths of the apothecia. 

 Doubtless the direction of discharge of the clouds of spores which 

 he saw was in part determined by the hehotropic curvatures of 

 the asci. 



Dr. Giissow's observations also suggest that his Aleuria vesiculosa 

 fruit-bodies puffed as a result of their becoming suddenly illuminated 

 or heated by a beam of sunhght. However, it is certain that 

 sunlight is not necessary for the puffing of A . vesiculosa ; for. in the 

 laboratory, ripe fruit-bodies of this species puff when removed from 

 damp air and brought into relatively dry air without any appreciable 

 change in the conditions of hght or heat. 



With a view to throwing further Ught on spore-discharge in the 

 Discomycetes it is desirable that Dr. Giissow's observations should 

 be extended, i.e. that particular fruit-bodies of various species 

 growing under perfectly natural conditions and untouched by man 

 should be studied throughout their spore-discharge period and that 

 the number of times they puff and the exact conditions under which 

 they puff should be recorded.^ 



The Heliotropism of the Asci and the Discharge of the Spores in 



Galactinia hsidia.. ^Galactinia badia is another large, commonly 



occurring, more or less hemispherical Discomycete (Fig. 146). It 



differs from Aleuria vesiculosa in habitat, for it is not coprophilous 



and grows on the ground in open or shady places in woods. I have 



gathered specimens at the Royal Gardens, Kew, and also at Minaki 



on the Lake of the Woods in central Canada. 



1 Among the Discomycetes that I have seen puff in the open as they were bemg 

 touched or gathered are : a Ciboria that grows on male Birch catkins, Ciliaria 

 scutellata, Galactinia badia, Rhizina inflata, and Urnula Craterium. Probably, had 

 these fruit-bodies been watched instead of being touched, sooner or later they would 

 have been seen to puff. 



