119 
found when the fungus is grown in pure culture on a nutrient 
medium. No attempt was made to elucidate the cytology of 
the process of development. The pycnidia originate as small 
Figs 4)—the sepa- 
The inner tissues are very delicate and show a radiate 
arrangement which is demarcated from a wall _ tissue. 
(Text Figs. Tb, c. - 
The central portion of this delicate tissue is very finely 
divided. For some considerable time the pycnidium is with- 
rown, a portion of the wall tissue of the pycnidium pad 
pi ly 
and externally. (Teat Fig. 7d. Pl. V., Fig. 5.) The amet 
j i the 
tissue which encloses the cnidium, but the tissue of the 
swollen portion of the wall is delicate, this being most marked 
In its a Ion. 2% 
is the first visible sign of orientation in the pycnidium, an 
pyenidium appears to be seated on a small stroma or basal pa 
of tissue. (Leet Fig. 7c,;-d, e, f.) At the same time folds of 
the wall grow into the central tissues. The wal 
py tig. 6. PE Vi veoPage. 4, 6.) These have ex- 
ceedingly delicate walls and are turgid, with a dense very 
finely granular protoplasm. The centre is filled with a 
the extremities of the basidia and being the first pycnospores. 
a 
the very delicate central cells 0 *‘ostiolar t ? and 
partly by the pressure exerted by the internal elements, which 
on the rupture of the ostiole pour forth in a diffuse mass. e 
peripheral layer of thick-walled brown cells originally covering 
the ostiole is either torn completely free—(Tert Fig. Th)—rup- 
tured—(T'ert Fig. if., Pl. I., Fig. 4)—or pushed over to one 
Side—(Text F; g- 7g). Pyenospore formation continues for some 
Considerable time after the first rupture of the ostiole. Not 
infrequently two or three pycnidia in immediate contiguity fuse 
