Stagonospora Cassavae n. spec. 
229 
liar forms of habitat of the Stagonospora Cassavae are rare. 
Tliey may not be used in the determination of the mould, for tliis pur- 
pose the Pycnides exclusively 
serve. 
A remarkable-Ascus for- 
ming is represented in fig. 8, 
also already in fig. 3 (the lo- 
west figure). We must posi- 
tively reconize two-different 
forms in the germ-mycelium: 
the normal mycelium and the 
sacculate (Ascus) forming one. 
This is clearly seen in fig. 3 
and 8. The very small 
Fig. 6. Different forms of local differentiated 
spore-reservoirs (proto-asci). x650. 
Fig. 7. Proto-asci forming of 
Stagonospora Cassavae. XÖ50. 
Fig. 8. Germinating endospore with ascus and asco- 
spores. xlO 000. 
Fig. 9. Pycnide of Stagono¬ 
spora Cassavae. x50. 
pycnides are leathery, pitch-black and round with a very faint not- 
ching of the upper surface, without subiculum and without an opening 
papilla: see fig. 9. These pycnides may become a source 
of errors in the determination. It is indeed an asto- 
nishingly long time before tliey are quite full 
grown. They are round only when in this full grown 
condition. Before that time only pycnidia-like bodies are 
met with, already provided with Conidies which 
may however liave all kinds of fantastic forms: a black 
kernel surrounded by a loose some what brownish tinted 
envelope. But this envelope also is more and more com- 
pressed in a centripetal direction, front which compression 
process after the lapse of time the full-grown pycnidiae result, so indeed 
as has been previously said conidia are already present in the pycnides 
Fig. 10. Pcynido- 
conidies of Sta- 
S'onospora Cassa- 
x 300. 
vae. 
