202 MR. A. D. COTTON ON 
in some cases there may be sixteen. A transverse section of the 
Nitophyllum frond shows that the zoosporangia lie in the wall of 
the host-plant in the same way as the vegetative cells described 
above. The zoospores as they are contained in the sporangium 
measure about 5 p in diameter; if sixteen zoospores are formed 
they are usually somewhat smaller. Fig. 2 shows a section of 
the frond of Nitophyllum, and sporangia are seen in various 
stages of development. The long axes of the sporangia may be 
parallel to the plane of the thallus or at right angles to it. 
As the sporangia mature, a minute beak-like outgrowth 1s 
formed which may protrude through the outer layers of the wall 
of the host. Through this beak-like outgrowth the spores are 
liberated. In Pl. 12. fig. 4 stages are given showing the projecting 
beak and also sporangia in which all the spores but one have 
been discharged. Entirely empty sporangia are very frequently 
met with. Attempts to observe the actual escape of the spores 
were unsuccessful, but in several cases spores were found 
attached to the Nitophyllum thallus sometimes in groups of 
three or four. The shape of the sporangia is variable, as is shown 
in fig. 3. 
The minute beak in the fruit of Endoderma may be compared 
with what is formed in the allied genus Pheophila. In the latter 
a tube is formed which may be of considerable size. 
The germinating spores of Endoderma are not frequently seen 
on N. Hillia. The endophyte forms large radiating patches 
and it appears to spread very readily by a purely vegetative 
method. But sections cut through the younger portions of the 
frond oceasionally show such spores, and the germ-tube may be 
readily noticed entering the cell-wall of the host. The method 
of germination appears to agree with that described by Huber 
for E. Jardinianum. When once an entrance has been gained, 
the plant assumes its usual endophytic habit. Though a very 
large number of sections were cut through the older parts of the 
Nitophyllum, no trace was ever seen ofa germinating Lndoderma ; 
it seems therefore probable that an entrance can only be obtained 
by the endophyte in the younger parts of the frond. Whether 
the sporelings can develope unless a suitable host be present 1s 
uncertain; and in any ease the plant has probably become too 
speeialised as an endophyte, to liveindependently for any length 
of time. That a certain amount of development, however, is not 
