686 Howard . — On Diplodia cacaoicola , P. Henn. ; 
elliptically shaped spores in all stages of development, and 
numerous paraphyses, are to be seen. The detailed structure 
of a pycnidium seen under the high power is shown in Fig. 3. 
It agrees closely with that described by Bauke 1 in the case 
of a Diplodia on Cornus sanguinea and figured in Zopf 2 . 
In cases when pieces of diseased cane, on which this Fungus 
was found, were placed in a moist chamber, it was observed 
that there was a considerable development of hair-like pro- 
cesses on the walls and round the opening of the pycnidium, 
giving the colonies a furry appearance which was never noted 
in the cane in ordinary circumstances. 
The spores are liberated from the mature pycnidium by 
means of a circular ostiole at the apex (Fig. 4), and are at 
first greyish and unicellular. In a short time, however, the 
exospore rapidly darkens and becomes dark brown, while at 
the same time a transverse wall is formed across the equator 
of the spore. The mature spores are very constant in size 
and measure 20 x 10/x. 
The development of the Fungus was next studied, starting 
from a single spore. No difficulty was experienced in obtain- 
ing hanging-drops containing a single spore by the method 
described by Marshall Ward 3 in his investigation on the 
ginger-beer plant. The spores germinated quite readily in 
such media as 15 to 20 per cent, gelatine raisin-extract or 
cane-juice, but the best results were obtained in the following 
food-material which is referred to later as the cane-extract 
medium : — 
Cane sugar 
Gelatine . 
5 grams. 
Tartaric acid . 
Peptone . 
Cane-extract . 
100 c. c. 
The cane-extract was obtained by soaking small pieces 
1 Beitr. z. Kenntniss der Pycnidien, Nova Acta, Bd. xxxviii, No. 5. 
2 Zopf, Die Pilze, p. 60. 
3 The Ginger-beer Plant and the organisms composing it. Phil. Trans. B., 
vol. 183, pp. 130-2, 1892. 
