334 BOTANICAL GAZETTE [NOVEMBER 
the secondary effects of fertilization. A longitudinal section 
through the female branch and young sporophyte of O. Macouni 
(jig. 4) shows this enlargement very clearly, and also shows how 
the bracts and perianth are inserted. The foot of the develop- 
ing sporophyte together with a portion of the stalk penetrate 
into this enlargement, which is composed in large part of food- 
storing cells. The capsule and the remainder of the stalk are 
covered by the calyptra, at the base of which may be seen.a few 
paraphyllia and unfertilized archegonia. In O. Macouni the 
enlargement is radial in structure, probably on account of the 
lateral attachment of the female branch. In such a species as 
O. prostratum, however, where the branches are very short and 
uniformly postical, the enlargement is not wholly symmetrical, 
but shows a slight bulging in the portion turned toward the 
substratum (fig. 42). In the related genus Adelocolea a very 
similar condition exists, and in certain species the bulging portion 
becomes more prominent and forms a bulbous base into which 
the foot of the erect young sporophyte forces its way. In the 
genus Marsupidium the extreme development of the enlarge- 
ment is found in the form of a cylindrical perigynium, in which 
practically the whole of the sporophyte is imbedded. 
It has already been noted that in O. Macounii the mouth of 
the perianth is wholly destitute of distinct teeth (fig. 2¢), and it 
“may be added that these are not invariably present in other species. 
On O. prostratum, for example, much of the perianth-mouth is 
scarcely crenulate (fig. 63), and it is only occasionally that a 
short tooth, one or two cells long, can be demonstrated. Even 
in O. Sphagni and in O. denudatum, the teeth are often reduced to 
slight crenulations. The fact that the perianth is irregularly 
lobed at the mouth and often deeply plicate makes it difficult to 
gain an accurate idea of the true conditions. The difficulty is 
increased by the withering of the upper part of the perianth and 
by its irregular laceration when the mature capsule is extruded. 
GEMMIPAROUS BRANCHES, 
In distinguishing the different species of Odontoschisma, the 
gemmiparous branches often yield characters of importance. In 
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