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CHAPTER I.

DROSERA ROTUNDIFOLIA, OR THE COMMON SUN-DEW.

Number of insects captured--Description of the leaves and their
appendages or tentacles-- Preliminary sketch of the action of the
various parts, and of the manner in which insects are
captured--Duration of the inflection of the tentacles--Nature of the
secretion--Manner in which insects are carried to the centre of the
leaf--Evidence that the glands have the power of absorption--Small size
of the roots.

During the summer of 1860, I was surprised by finding how large a
number of insects were caught by the leaves of the common sun-dew
(Drosera rotundifolia) on a heath in Sussex. I had heard that insects
were thus caught, but knew nothing further on the subject.* I

* As Dr. Nitschke has given ('Bot. Zeitung,' 1860, p. 229) the
bibliography of Drosera, I need not here go into details. Most of the
notices published before 1860 are brief and unimportant. The oldest
paper seems to have been one of the most valuable, namely, by Dr. Roth,
in 1782. There is also an interesting though short account of the
habits of Drosera by Dr. Milde, in the 'Bot. Zeitung,' 1852, p. 540. In
1855, in the 'Annales des Sc. nat. bot.' tom. iii. pp. 297 and 304, MM.
Groenland and Trcul each published papers, with figures, on the
structure of the leaves; but M. Trcul went so far as to doubt whether