Howard.—On a Disease of Tradescantia . 29 
septate, cylindrical main axis, "some xo/x or so thick and 
1-3 or more mm. long, from which are put forth acropetally 
and at right angles, peg-like branches about 5 ju thick in the 
middle, and 50 \i or more long (Fig. 11). Each of these 
pedicels tapers below to its insertion in the axis, and widens 
above into a club-shaped head about 10 \i thick. The head 
puts forth four or five irregularly swollen sterigmata, each 
about 1 o~i ifi long, whence clusters of spores (conidia) bud 
out, as in Botrytis (see Figs. 11 and 12). The conidia are 
ovoid or globoid, and average 4-5 1a in diameter. All the 
parts—mycelium, axis, heads, and capitula, and spores—are 
colourless, and glisten like silver or white floss silk in the 
mass, and the sum of the characters brings this Fungus into 
Corda’s genus Botryosporium 1 . 
The fertile hyphae grow down into the air below the drop 
and appear in the air darker than the submerged sterile 
hyphae. They vary in length between wide limits, are rarely 
branched, and give off lateral branchlets of equal length in 
a racemose manner- as described. Each branchlet ends In a 
clavate swelling, which bears three or four circular appendages, 
which in turn bear the conidia, the whole forming a nearly 
globose head of spores. 
During the formation of conidia the fertile hyphae were 
seen to bear globular bodies resembling gas-bubbles (Figs. 4,5), 
the nature of which was not determined 2 . In many cases 
a head of conidia was seen to be encased in one of these 
£ bubbles,’ and on several occasions, when such heads came 
in contact with the cover-slip, the ‘bubble’ burst, and the 
conidia were thrown some distance. It would thus appear 
as if these bodies are useful in spore-distribution. Such 
liberated spores were found to have a small circular body 
attached to one end, and it appeared probable that this 
structure served as an abjunctor to free the spore from the 
1 See Saccardo, Sylloge Fungorum, Vol. iv, p. 54, and Massee, Brit. Fungus 
Flora, Vol. iii, p. 291. 
2 Such gas-bubbles are very commonly found on conidiophores in the act of 
developing spores. The gas is probably enclosed in a slimy matrix ; see Brefeld, 
Unters. aus dem ges. Geb. der Mycol., Heft 10, p. 177 and Plate V, Fig. 42. 
