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Mycologia 



are about 90-140 X 100-190 /x. The asci are clavate, 12-14 X 

 60-80 ju,, with the ascus wall thickened at the apex {fig. i). This 

 thickened apex is ruptured when the spores are shot out {fig. 2). 



Figs. 6, 7. Apothecia of Trochila Populorum. X 330. 6. Young stage. 

 7. Nearly mature stage. 



The spores are hyaline, one-celled, 12-16 X 5-7-2 /x, almost always 

 containing two large guttulae, one at each end of the spore. The 

 paraphyses are very abundant, 80-100, long, narrow, septate, and 

 somewhat broadened at the apex. 



