106 OUTDOOR STUDIES 
does not conform its habits precisely to those 
of any of them. Its great black roots, some- 
times as large as a man’s arm, form a network 
at the bottom of the water. Its stem floats, an 
airy four-celled tube, adapting itself to the depth, 
and stiff in shallows, like the stalk of the yellow 
lily; and it contracts and curves downward 
when seedtime approaches. The leaves show 
beneath the magnifier beautiful adaptations of 
structure. They are not, like those of land 
plants, constructed with deep veins to receive 
the rain and conduct it to the stem, but are 
smooth and glossy, and of even surface. The 
leaves of land vegetation have also thousands 
of little breathing-pores, principally on the un- 
der side: the apple leaf, for instance, has twenty- 
four thousand to the square inch. But here 
they are fewer; they are wholly on the upper 
side, and, whereas in other cases they open or 
shut according to the moisture of the atmo- 
sphere, here the greedy leaves, secure of mois- 
ture, scarcely deign to close them. Neverthe 
less, even these give some recognition of 
hygrometric necessities, and, though living on 
the water, and not merely christened with dew- 
drops like other leaves, but baptized by immer- 
sion all the time, they are yet known to suffer 
in drought and to take pleasure in the rain. 
After speaking of the various kindred of the 
