The cause of these currents seems to
lie in contractions of the protoplasm which bounds the channels in which
they flow, but which are so minute that the best microscopes show only
their effects, and not themselves.
The spectacle afforded by the wonderful energies prisoned within the
compass of the microscopic hair of a plant, which we commonly regard
as a merely passive organism, is not easily forgotten by one who has
watched its display, continued hour after hour, without pause or sign
of weakening. The possible complexity of many other organic forms,
seemingly as simple as the protoplasm of the nettle, dawns upon one;
and the comparison of such a protoplasm to a body with an internal
circulation, which has been put forward by an eminent physiologist,
loses much of its startling character. Currents similar to those of
the hairs of the nettle have been observed in a great multitude of
very different plants, and weighty authorities have suggested that
they probably occur, in more or less perfection, in all young vegetable
cells. If such be the case, the wonderful noonday silence of a tropical
forest is, after all, due only to the dulness of our hearing; and could
our ears catch the murmur of these tiny Maelstroms, [96] as they whirl
in the innumerable myriads of living cells which constitute each tree,
we should be stunned, as with the roar of a great city.
Pages:
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160