INSECTIVOROUS PLANTS. 
CHAPTER I. 
DrosERA ROTUNDIFOLIA, OR THE COMMON SUN-DEW. 
Number of insects captured— Description of the leaves and theiz 
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 secre- 
tion — 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. 
Durine the summer of 1860, I was surprised by find- 
ing 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 
oue 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 1°55, in the‘ An- 
nales des Se. nat. bot.’ tom. iii. pp. 
297 and 30+, MM. Greenland and 
Tréculeach published papers, with 
figures, on the structure of the 
leaves; but M. Trécul went so 
far as to doubt whether they pos- 
sessed any power of movement. 
Dr. Nitschke’s papers in the ‘ Bot. 
Zeitung’ for 1860 and 1861 are 
by far the most important ones 
which have been published, both 
on the habits and structure of 
this plant; and I shall frequently 
have occasion to quote from 
them. His discussions on several 
points, for instance on the trans- 
mission of an excitement from one 
part of the leaf to another, are 
excellent. On Dec. 11, 1862, Mr. 
J. Scott read a paper before the 
Botanical Society of Edinburgh, 
