terior tentacles increasing in length in due proportion, as they stand nearer to the circumference.
The kind of inflection which the tentacles undergo is best shown when the gland of one of the long exterior tentacles is in any way excited; for the surrounding ones remain un-
Fig. 4. Leaf (enlarged) with all the tentacles closely inflected, from immersion in a solution of ammonia (one part to 87,500 of water). |
Fig. 5. Leaf (enlarged) with the tentacles on one side inflected over a bit of meat placed on the disc. |
affected. In the accompanying outline (Fig. 6) we see one
tentacle, on which a particle of meat had been placed, thus
bent towards the centre of the leaf, with two others retaining
their original position. A gland may be excited by being
simply touched three or four times, or by prolonged contact
with organic or inorganic objects, and various fluids. I have
distinctly seen, through a lens, a tentacle beginning to bend
in ten seconds, after an object had been placed on its gland;
and I have often seen strongly pronounced inflection in under
one minute. It is surprising how minute a particle of any
substance, such as a bit of thread or hair or splinter of glass,
if placed in actual contact with the surface of a gland, suffices
to cause the tentacle to bend. If the object, which has