PUFFING IN THE DISCOMYCETES 241 



falling, appeared to be mature but could not be caused to puff 

 in the open, presumably owing to their being too cold. The 

 fruit-bodies were put into a vasculum and taken to the laboratory 

 the air of which had a temperature of about 70° F. As soon as 

 the laboratory had been entered, the fruit-bodies were removed 

 from the vasculum, separated from one another, and placed in a 

 series of Petri dishes. During these operations not a single fruit- 

 body puffed. However, after an hour, when the fruit-bodies had 

 become warmed up to the temperature of the room, puffing occurred 

 freely whenever a mature fruit-body was removed from a Petri dish 

 and exposed to the relatively dry room-air. Advantage was taken 

 of this fact to observe the direction and distance of discharge of 

 three particular fruit-bodies. In turn, each was quickly removed 

 from its Petri dish with the fingers and held horizontally in the air 

 of the laboratory. Within two seconds from the beginning of this 

 operation puffing took place. The spore-cloud produced by each 

 fruit-body travelled forward horizontally (c/. Fig. IIG). One of the 

 spore-clouds went 8 cm. before dispersing irregularly, another 

 12 cm., and another 17 cm. ( = 7 inches). 



The results yielded by the experiments just described prompted 

 the following question : the apothecia being campanulate in form, 

 how comes it that the spores are shot straight out of the cup in a 

 direction more or less parallel to the cup's axis ? To solve this 

 problem it was necessary to ascertain : (1) the exact shape of the 

 apothecium at the moment of puffing, (2) the arrangement of the 

 asci in the hymenium, and (3) the manner in which the asci 

 open. 



Variations in the shape of the apothecium, nearly three times the 

 natural size, are shown in Fig. 117. At A is an end-view and at 

 B a vertical section of a young apothecium which is about to expand. 

 Its hymenium, as indicated in B, was lining the cavity of the cup, 

 but the asci had not yet developed any spores. C is a well-expanded 

 apothecium seen from above. Its dark central cavity was hned by 

 a deep-scarlet hymenium containing ripe ascospores, whilst the lighter 

 marginal crenations were orange-yellow and sterile. The six draw- 

 ings D-I show vertical sections through six apothecia which had 

 discharged or were about to discharge their spores. The average 



VOL. VI. ^ 



