Evans. — Branching in the Leafy Hepaticae. 
2 9 
of leaf and branch, although the latter may always be described as axillary. 
In the common Plagiochila asplenioides , for example, Servi't (W, Fig. 3) 
figures a branch much nearer the middle of a leaf than is shown above, 
while in the South American Anomoclada mucosa , as well as in certain species 
of Odontoschisma , the lateral branches are close to the dorsal margins of 
the leaves. In all these cases, so far as examined, the branch-spirals and 
the sequences of the branch-leaves exhibit as great an irregularity as in 
Micropterygium and the other genera with complicate leaves. 
The ruptured cortical sheath at the base of a lateral intercalary branch 
is usually conspicuous, but aside from this the basal structures show no very 
striking modifications. In most cases the first few cycles of leaves are 
rudimentary and often more or less displaced from their theoretical positions. 
As the branch develops the leaves gradually become more and more definite 
in position and in form, and the branch soon acquires the appearance 
Fig. 36. Bazzania Brighami. Oahu, Hawaiian Islands (C. M. Cooke, Jun.). x 40. 
characteristic of the species. Occasionally, as in Cephaloziella Tiirneri , 
a species of Europe, Africa, and North America, the base of a branch bears 
underleaves, even although these are absent from fully developed shoots. 
The modifications mentioned are apparently all reversionary in character. 
Intercalary branches arising from ventral segments are far more common 
than those just described and have been less subject to discussion. Certain 
genera, such as Herberta , An as trophy llum , and Saccogyna, seem to branch 
invariably in this way, and the same thing is true of many species of 
Cephalozia and Odontoschisma. In other cases ventral branches of this type 
occur in connexion with lateral intercalary branches, as in Cephaloziella 
Turneri , or with terminal branches, as in the genera Lepidoziaand Bazzania. 
When found in connexion with lateral branches the ventral branches are 
usually specialized in some way. In Lepidozia , for example, the ventral 
branches are almost always sexual, while in Bazzania they are mostly sexual 
or flagelliform. Even in this latter genus, however, ventral branches with 
normal leaves are occasionally produced, and Fig. 36, which is drawn from 
