1903] ODONTOSCHISMA MACOUNII AND ITS ALLIES 337 
emphasized for Anomoclada. The vegetative branches are occa- 
sionally lateral (fig. 65), but rarely recede very far from the pos- 
tical base of the subtending leaf: so far as observed, the female 
branches are invariably postical. The only character of real 
importance which distinguishes Anomoclada from Odontoschisma 
is its antical branching. Whether this peculiarity by itself is 
sufficient to separate genera may well be questioned, especially 
when we take into account the great variability in the branching 
of Odontoschisma. 
One of the connecting links between Odontoschisma and 
Cephalozia is C. Francisci,a rare species known from several 
localities in western Europe and recently detected in Maine.” It 
was, to a considerable extent, the existence of this species which 
influenced Spruce in including Odontoschisma among his sub- 
genera of Cephalozia. C. Francisci is a true Cephalozia and has 
bifid leaves, but the lobes of the latter are commonly rounded or 
obtuse, instead of being sharp-pointed as is usual in the genus. 
Similar bifid leaves with rounded lobes are exceptionally found 
in Odontoschisma Sphagni, as Spruce has already noted, and they. 
are not infrequent in O. prostratum (fig. 43). C. Francisci agrees 
with Odontoschisma further in its postical flagella, and in its 
irregularly bifid underleaves, the latter being built up on essen- 
tially the same plan as in O. Sphagni and bearing a very few 
secondary marginal papillae of short duration. The only char- 
acters which separate this species from Odontoschisma are its 
smaller size, its more delicate structure, and its regularly bifid 
leaves, not one of which can be regarded as of very great moment. 
In fact, the second of these differences is hardly worthy of 
mention, because the cell walls of C. Francisci, although thinner 
than is usual in Odontoschisma, are by no means wholly destitute 
of thickenings; these appear in the leaves as minute but distinct 
trigones, in the involucral leaves and perianths as more or less 
uniform thickenings tending to obliterate the trigones. 
It will be seen, therefore, that although Odontoschisma rep- 
resents a natural group of closely allied species, there is, on the 
one hand, a very vague line of demarcation between Odonto- 
79 Cf. Miss C. C. HAYNES, Torreya 3:41. 1903. 
