equal length. No prey could be seen within these minute bladders. As
the rhizomes of this species were furnished with bladders, those of
Genlisea africana, ornata, and aurea were carefully [page 452]
examined, but none could be found. What are we to infer from these
facts? Did the three species just named, like their close allies, the
several species of Utricularia, aboriginally possess bladders on their
rhizomes, which they afterwards lost, acquiring in their place
utriculiferous leaves? In support of this view it may be urged that the
bladders of Genlisea filiformis appear from their small size and from
the fewness of their quadrifid processes to be tending towards
abortion; but why has not this species acquired utriculiferous leaves,
like its congeners?
CONCLUSION.
It has now been shown that many species of Utricularia and of two
closely allied genera, inhabiting the most distant parts of the
world Europe, Africa, India, the Malay Archipelago, Australia, North
and South America are admirably adapted for capturing by two methods
small aquatic or terrestrial animals, and that they absorb the products
of their decay.
Ordinary plants of the higher classes procure the requisite inorganic
elements from the soil by means of their roots, and absorb carbonic
acid from the atmosphere by means of their leaves and stems. But we
have seen in a previous part of this work that there is a class of
plants which digest and afterwards absorb animal matter, namely, all
the Droseraceae, Pinguicula, and, as discovered by Dr. Hooker,
Nepenthes, and to this class other species will almost certainly soon
be added. These plants can dissolve matter out of certain vegetable
substances, such as pollen, seeds, and bits of leaves. No doubt their
glands likewise absorb the salts of ammonia brought to them by the
rain. It has also been shown that some other plants can absorb ammonia
by [page 453] their glandular hairs; and these will profit by that
brought to them by the rain. There is a second class of plants which,
as we have just seen, cannot digest, but absorb the products of the
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