FIG. 8. (Drosera rotundifolia.) Diagram of the same cell of a tentacle,
showing the various forms successively assumed by the aggregated masses
of protoplasm.
here represented (fig. 8) was from this leaf, being sketched eight
times in the course of 15 m. These sketches exhibit some of the more
remarkable changes which the protoplasm undergoes. At first, there was
at the base of the cell 1, a little mass on a short footstalk, and a
larger mass near the upper end, and these seemed quite separate.
Nevertheless, they may have been connected by a fine and invisible
thread of protoplasm, for on two other occasions, whilst one mass was
rapidly increasing, and another in the same cell rapidly decreasing, I
was able by varying the light and using a high power, to detect a
connecting thread of extreme tenuity, which evidently served as [page
42] the channel of communication between the two. On the other hand,
such connecting threads are sometimes seen to break, and their
extremities then quickly become club-headed. The other sketches in fig.
8 show the forms successively assumed.
Shortly after the purple fluid within the cells has become aggregated,
the little masses float about in a colourless or almost colourless
fluid; and the layer of white granular protoplasm which flows along the
walls can now be seen much more distinctly. The stream flows at an
irregular rate, up one wall and down the opposite one, generally at a
slower rate across the narrow ends of the elongated cells, and so round
and round. But the current sometimes ceases. The movement is often in
waves, and their crests sometimes stretch almost across the whole width
of the cell, and then sink down again. Small spheres of protoplasm,
apparently quite free, are often driven by the current round the cells;
and filaments attached to the central masses are swayed to and fro, as
if struggling to escape. Altogether, one of these cells with the ever
changing central masses, and with the layer of protoplasm flowing round
the walls, presents a wonderful scene of vital activity.
[Many observations were made on the contents of the cells whilst
undergoing the process of aggregation, but I shall detail only a few
cases under different heads. A small portion of a leaf was cut off,
placed under a high power, and the glands very gently pressed under a
compressor. In 15 m. I distinctly saw extremely minute spheres of
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