covered with [page 330] upcurved prickles; they terminate
also in two straight little prickles. The bilobed
leaves are, I believe, larger and certainly broader
even than those of the Australian form; so that the
greater convexity of their margins was conspicuous.
The length of an open leaf being taken at 100, the
breadth of the Bengal form is nearly 173, of the Australian
form 147, and of the German 134. The points on
the infolded margins are like those in the Australian
form. Of the few leaves which were examined,
three contained entomostracan crustaceans.
Concluding Remarks.—The leaves of the three
foregoing closely allied species or varieties are
manifestly adapted for catching living creatures.
With respect to the functions of the several parts,
there can be little doubt that the long jointed hairs
are sensitive, like those of Dionaea, and that, when
touched, they cause the lobes to close. That
the glands secrete a true digestive fluid and afterwards
absorb the digested matter, is highly probable from
the analogy of Dionaea,—from the limpid
fluid within their cells being aggregated into spherical
masses, after they had absorbed an infusion of raw
meat,—from their opaque and granular condition
in the leaf, which had enclosed a beetle for a long
time,—and from the clean condition of the
integuments of this insect, as well as of crustaceans
(as described by Cohn), which have been long captured.
Again, from the effect produced on the quadrifid processes
by an immersion for 24 hrs. in a solution of urea,—from
the presence of brown granular matter within the quadrifids
of the leaf in which the beetle had been caught,—and
from the analogy of Utricularia,—it is
probable that these processes absorb excrementitious
and decaying animal matter. It is a more curious
fact that the points on [page 331] the infolded margins
apparently serve to absorb decayed animal matter in
the same manner as the quadrifids. We can thus
understand the meaning of the infolded margins of the
lobes furnished with delicate points directed inwards,
and of the broad, flat, outer portions, bearing quadrifid
processes; for these surfaces must be liable to be
irrigated by foul water flowing from the concavity
of the leaf when it contains dead animals. This
would follow from various causes,—from
the gradual contraction of the concavity,—from
fluid in excess being secreted,- -and from the generation
of bubbles of air. More observations are requisite
on this head; but if this view is correct, we have
the remarkable case of different parts of the same
leaf serving for very different purposes—one
part for true digestion, and another for the absorption
of decayed animal matter. We can thus also understand
how, by the gradual loss of either power, a plant might
be gradually adapted for the one function to the exclusion
of the other; and it will hereafter be shown that
two genera, namely Pinguicula and Utricularia, belonging
to the same family, have been adapted for these two
different functions. [page 332]
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