338 BOTANICAL GAZETTE [NOVEMBER 
schisma and Anomoclada, and, on the other hand, a similarly 
vague line between Odontoschisma and Cephalozia. Ina certain 
sense our species of Odontoschisma form part of a continuous 
series, whose extremes are Anomoclada mucosa and Cephalozia 
Francisct. If we recognize three distinct genera in this series, it 
is largely because the two extremes are so very diverse. In the 
large group of the Lejeuneae we find these conditions duplicated, 
many of the recognized genera being connected by intermediate 
species. 
DESCRIPTION OF SPECIES WITH NOTES ON GEOGRAPHICAL 
DISTRIBUTION. 
Full descriptions of O. Macourlii, O. Gibbsiae, and O. prostratum 
are appended. 0. Portoricense is also described, although the 
present paper makes no pretense of revising the species of 
Odontoschisma found in the American tropics. For descriptions 
of O. denudatum and O. Sphagni, aside from the characters dis- 
cussed in the preceding pages, reference may be made to the 
writings of Lindberg,? of Spruce,3* and of Pearson.3? For all 
five of our northern species the synonymy and geographical 
distribution are noted, and the following artificial key will aid in 
their identification: 
1. Plants commonly growing on rotten logs or on banks, branches varying 
from postical to lateral, leaves more or less a concave, not 
margined, gemmiparous branches often abundan a 
Plants, commonly growing in bogs or swamps, en hess satel 
leaves plane or slightly concave, more or less saciid margined, 
emmiparous branches wanting - - s 
Leaves and underleaves on the sccrseee ala branches suberect, strongly 
concave and imbricated - - 
Leaves and underleaves on the pegasus branches squarrose, hie or 
slightly concave and distant - 3. O. denudatum 
mt 
, 
¥ 
3. Plants pale green or yellowish, leaves not dilated at the postical base, 
median leaf-cells averaging 28 in diameter, underleaves distinct and 
frequently conspicuous - - - 1. O, Macounit 
3. Plants varying from pale green to reddish or brownish, leaves dilated at 
the postical base, median leaf-cells averaging 1g «in diameter, under 
leaves usually minute and inconspicuous - - - 2. O, Gibbsiae 
® Notis. ur Sallsk. pro F. et Fl. Fenn, Férhandl. 13: 357-360. 1874. 
* Journal of Botany §: 166, 193. 1876. On Cephalozia 60, 61. 1882. 
% Hep. British Isles 171, 174. 1900. 
