attached not to one margin, but to the bottom. The
* Gardener s Chronicle, 1874, p. 209. [page 285]
inner surface and the edges of the cups are studded with tentacles,
which include fibro-vascular bundles, rather different from those seen
by me in any other species; for some of the vessels are barred and
punctured, instead of being spiral. The glands secrete copiously,
judging from the quantity of dried secretion adhering to them. [page
286]
CHAPTER XIII.
DIONAEA MUSCIPULA.
Structure of the leaves Sensitiveness of the filaments Rapid movement
of the lobes caused by irritation of the filaments Glands, their power
of secretion Slow movement caused by the absorption of animal
matter Evidence of absorption from the aggregated condition of the
glands Digestive power of the secretion Action of chloroform, ether,
and hydrocyanic acid The manner in which insects are captured Use of
the marginal spikes Kinds of insects captured The transmission of the
motor impulse and mechanism of the movements Re-expansion of the lobes.
This plant, commonly called Venus fly-trap, from the rapidity and
force of its movements, is one of the most wonderful in the world.* It
is a member of the small family of the Droseraceae, and is found only
in the eastern part of North Carolina, growing in damp situations. The
roots are small; those of a moderately fine plant which I examined
consisted of two branches about 1 inch in length, springing from a
bulbous enlargement. They probably serve, as in the case of Drosera,
solely for the absorption of water; for a gardener, who has been very
successful in the cultivation of this plant, grows it, like an
epiphytic orchid, in well-drained damp moss without any soil.** The
form of the bilobed leaf, with its foliaceous footstalk, is shown in
253