zone of transparent fluid as in the case of those undergoing digestion.
Other cubes retained their angles and white colour. After eight days
all were somewhat reduced in size, discoloured, with their angles much
rounded. Nevertheless in four out of the five specimens, the central
parts were still white and opaque. So that their state differed widely,
as we shall see, from that of the cubes subjected to the action of the
secretion.
[Experiment 1.
Rather large cubes of albumen were first tried; the tentacles were well
inflected in 24 hrs.; after an [page 93] additional day the angles of
the cubes were dissolved and rounded;* but the cubes were too large, so
that the leaves were injured, and after seven days one died and the
others were dying. Albumen which has been kept for four or five days,
and which, it may be presumed, has begun to decay slightly, seems to
act more quickly than freshly boiled eggs. As the latter were generally
used, I often moistened them with a little saliva, to make the
tentacles close more quickly.
Experiment 2. A cube of 1/10 of an inch (i.e. with each side 1/10 of an
inch, or 2.54 mm. in length) was placed on a leaf, and after 50 hrs. it
was converted into a sphere about 3/40 of an inch (1.905 mm.) in
diameter, surrounded by perfectly transparent fluid. After ten days the
leaf re-expanded, but there was still left on the disc a minute bit of
albumen now rendered transparent. More albumen had been given to this
leaf than could be dissolved or digested.
Experiment 3. Two cubes of albumen of 1/20 of an inch (1.27 mm.) were
placed on two leaves. After 46 hrs. every atom of one was dissolved,
and most of the liquefied matter was absorbed, the fluid which remained
being in this, as in all other cases, very acid and viscid. The other
cube was acted on at a rather slower rate.
Experiment 4. Two cubes of albumen of the same size as the last were
placed on two leaves, and were converted in 50 hrs. into two large
drops of transparent fluid; but when these were removed from beneath
the inflected tentacles, and viewed by reflected light under the
microscope, fine streaks of white opaque matter could be seen in the
one, and traces of similar streaks in the other. The drops were
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