1903] ODONTOSCHISMA MACOUNII AND ITS ALLIES 325 
GENERIC CHARACTERS, 
The generic characters ascribed by Schiffner to Odonto- 
schisma are those accepted by the majority of recent writers, 
whether they regard the group as a genus or merely as a sub- 
genus under Cephalozia. The most important of these characters 
are the following: 
Plants rather large, growing in tufts, varying from green 
to red or dark brown; stems creeping, radicelliferous, not 
arising from a rhizome; branching uniformly postical; leaves 
succubous, entire, obliquely or longitudinally inserted, varying in 
outline from orbicular to ovate, rarely emarginate at the apex, 
cell walls thickened ; underleaves small ; 2 inflorescence ona short 
branch; perianth hypogonianthous, dentate or ciliate at the con- 
tracted mouth; capsule oval. 
All of these characters apply pretty definitely to O. Sphagni 
and also to O. prostratum. In our other species, however, 
the branching exhibits considerable variation, especially in O. 
Macountt. In this species, moreover, the mouth of the perianth 
is entire or nearly so, and the underleaves often attain a con- 
siderable size. Underleaves, in fact may be demonstrated in all 
our species, and although they are sometimes small and transi- 
tory in their nature, they afford nevertheless differential char- 
acters of considerable importance. 
BRANCHING. 
The branching in Odontoschisma is always intercalary in 
character, using this term in the sense suggested by Leitgeb.”* 
According to this author, intercalary branches arise almost 
invariably from the postical segments of an axis. This origin 
is seen very clearly in Kantia and in the typical species of 
Cephalozia. It is also seen in the flagella and in the sexual 
branches of Bazzania. In Odontoschisma the postical origin of 
the branches may be demonstrated in the normal flagella of all 
our species (fig. gg) and also in. the vegetative and sexual 
branches of O. Sphagni and O. prostratum (fig. 42). In O. 
Macounit, however, the leafy branches and also the sexual 
** Unters, iiber Lebermoose 2:21. 1875. 
