38 Farmer.— Studies in Hepaticae: 
formation of the frond agrees with that form of dichotomy, so 
common in Hepatics, in which the original apex ceases to 
segment, and is replaced by two fresh apices arising right and 
left of it. This takes place repeatedly, and so the expanded 
branch-system or frond is formed. When an underground 
shoot is about to grow up out of the ground, it changes its 
shape, and from being circular in transverse section, it becomes 
elliptical, and wings appear on the two edges, which eventually 
spread out and form the laminae on either side of the mid-rib 
of the thallus. 
The branching in the subterranean portion of the plant is 
very much complicated by the fact that the apical cells of 
lateral axes do not develop immediately they are differentiated, 
but usually remain dormant often for a considerable time. 
These ‘ eyes,’ or resting buds, are constantly met with in 
sections near the apex of rhizome-branches, and it becomes 
a matter of considerable difficulty to tell whether the case is 
one of dichotomy or of monopodial lateral branching. It is 
certain however that if a dichotomy exists, it does not 
resemble the ordinary Hepatic type, for there can be no 
question of the replacement of one apex by two fresh ones ; 
the original apical cell of the shoot is not obliterated, but con- 
tinues to remain active, at any rate until its shoot issues from 
the soil. The view I have been led to adopt, after examining 
a somewhat large number of preparations, is that the branch- 
ing in the underground shoots is strictly lateral. The apical 
cells of the lateral axes are formed at a very early period in 
the history of the segment cut off from the apical cell ; they 
may even appear as the result of its first division, which cuts 
off an inner from an outer cell, the latter forming the new 
apical cell of the lateral axis. These new apical cells never, 
so far as I have observed them, develop at once, although 
they sometimes form one or two divisions, after which the 
large cell, whose size and relative richness in protoplasm mark 
it out from the surrounding ones, either remains dormant for 
a time, or, as is still more frequently the case, it does not 
develop any further at all. 
