PLATE 5 b 
A. —Pycnidia on a strawberry; only buffer tissue visible. 
B. — J Characteristic growth of mycelium on agar; pycnidia at first formed in con¬ 
centric circles. 
C. —Pycnidia from similar cultures more highly magnified, showing manner in 
which buffer tissue splits open frequently in the form of a cross. 
D. —In older cultures many pycnidia cluster about the large one first formed at the 
center. 
E. —Buffer tissue seen to be composed of cells originating from the upper portion 
of the outer wall of the pycnidium. 
F. —-Large perithecia from a leaf of Rosa , sp. They show the same peculiar splitting 
of the buffer tissue. Mature ascocarps always collapse when dry. 
G. —Upper portion of a young perithecium, showing buffer tissue and conical 
ostiole; opening not yet completed. 
H. —-Similar to the preceding; opening in the ostiole nearly completed. 
I. —Buffer tissue has dried up and broken away. Ascospores just forming; np 
paraphyses are ever present. 
J. —Shows the falcate periphyses lining the ostiole—two branches from each cell. 
K. —Mature ascocarp; remains of buffer tissue still present. 
ft Figures B and C are from photographs by Marguerite Ickis. 
