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manner of the sphagnum. Along most of the stem these branch 
clusters are scattered, but toward the tip they usually grow so 
close together as to form a rather compact rosette which some- 
times is mistaken for a flower. It might be added that the bran- 
ches in each cluster are of two sorts: one kind stands out at right 
angles to the main axis; the other kind droops down alongside the 
n t only is the arrangement of the branches on the ste 
distinctive. Quite as striking is the arrangement of the leaves 
the bi es. Every branch is completely covered over by a 
series of tiny, more or less spoon-shaped leaves, which closely 
overlap one ai somewhat after the manner of shingles on 
the roof of a hou 
To what pene en does the sphagnum owe its 
efficiency as an absorbent? 
To a limited degree certain of the features already described 
adapt the sphagnum to absorb liquids: the close overlapping of 
the leaves around the branches, and the sponge-like matting of 
the pendent branches around the stem. But the real secret of 
the ephagnuay s seape as an absorbent lies in the remarkable 
its leave 
ome discussing the somewhat complicated sphagnum leaf, 
of a single layer of tiny microscopic cells. Seen in surface view 
the individual cells are polygonal in outline, but in reality, con- 
sidered as solids, they are prismatic in shape. All of the cells in 
they are green and living and they are all of approximately the 
same size and shape. 
But in a sphagnum leaf the structure is much more complex 
Here also there is just a single layer of cells, but these cells are 
of two totally different kinds. First, as in the ordinary moss 
leaf, there are the green, living cells. But these green cells, in 
w 
through the leaf. In the meshes of this network occurs the 
