324 BOTANICAL GAZETTE [NOVEMBER 
sections to generic rank, the section Pleuroschismotypus becom- 
ing the genus Pleuroschisma in its restricted sense. Two species 
of Odontoschisma, O. Sphagni and O. denudatum, are recognized. 
In the Synopsis Hepaticarum Nees von Esenbeck*s redescribed 
the genus under the name Sphagnoecetis. He recognized but a 
single European species, S. communis, which was made to include 
‘both of Dumortier’s species. Two exotic species, however, are 
doubtfully referred to the genus, and three other exotic species 
are added in the appendix. 
In 1874 Lindberg*™ revised the European species of Odonto- 
schisma and clearly distinguished between O. Sphagni and 0. 
denudatum. Unfortunately he included in the genus Jungermannia 
decipiens Hook., a species which Mitten had placed in his genus 
Adelanthus’*? (now Adelocolea). In his paper on Anomoclada, 
published two years later, Spruce*® showed clearly why Adelan- 
thus should not be included in Odontoschisma. At the same 
time he fully described the two European species of the latter 
genus and ascribed to both a very wide geographical distribution, 
extending, in fact, into the tropics of South America, In 1877 
Trevisan”? accepted the genus Odontoschisma in Lindberg’s wide 
sense, and included in it eleven species, most of them exotic. 
In 1882 Spruce” reduced Odontoschisma to a subgenus under 
Cephalozia, on account of the close resemblance between their 
sexual branches and sporophytes, and he continued so to regard 
it during the remainder of his life. He was followed in this by 
Lindberg and by Arnell, as well as by Pearson and by several 
other hepaticologists of the English school. On the continent, 
however, and in America, this extreme view has never met with 
much favor, and Schiffner, in his treatment of the Hepaticae for 
Engler and Prantl’s Die natiirlichen Pflanzenfamilien, published in 
1893, restored Odontoschisma to generic rank. Schiffner esti- 
mates the number of species of Odontoschisma at thirteen, and 
very few additions have been made up to the present time. 
5G. L. & N. Syn. Hep. 148. 1845. 
*6Notis. ur Sallsk. pro F. et Fl. Fenn. Férhandl. 13:357. 1874. 
*7 Jour. Linn. Soc. Bot. 7:244. 1864. 9 Mem. R. Ist. Lomb. III. 4: 418. 1877- 
*8Jour. Bot. 5: 166. 1876. 20° On Cephalozia 59. 1882. 
