INSECT DEVOURING PLANTS. 221 
digested and assimilated, but that plants had no such organ, but 
absorbed through their rootlets and through their leaves certain 
chemical substances from the earth and air, which were elaborated 
in the cells of their leaves and stems, and thus supplied food 
necessary for the growth and existence of the plants. It was 
afterwards discovered that certain foreign plants, such as Venus’ fly 
trap and the pitcher plants, caught in their flowers flies and other 
insects, which in time became softened and then disappeared 
altogether, having actually been digested and absorbed by the cells 
existing inside the flower. Since then some of our common plants, 
such as we can procure in our immediate neighbourhood in the 
summer, have also been proved to have the same property, not, 
however, in their flowers, but in their leaves. It is to these, 
specimens of which I have here, I wish to draw your attention 
this evening. The most common of these plants is found at 
Burnham Beeches, close by the small pond at the extreme corner, 
in a damp, boggy situation; it is also found at Virginia Water, 
Bagshot Heath, and many other damp localities. The name of 
the plant is Lindew, Drosera rotundifolia, belonging to the natural 
order Droseracez, and nearly allied to the Violet tribe. There 
are three kinds of Drosera in England—the round-leaved, inter- 
mediate, and long-leaved. The plants when growing are very in- 
conspicuous, for the leaves lie close to the earth, or are almost 
imbedded in mosses and other small plants growing about them. 
ee I have here two species of Drosera, the ‘ round-leaved’ 
and the ‘intermediate.’ The tentacles are somewhat flattened, 
and are formed of several rows of cells, which surround a spiral 
vessel which passes through their whole length. The cells contain 
a purplish fluid, filled with granular matter, which under the micros- 
cope can be seen in constant motion. The glands themselves are 
covered with a glutinous substance, which is poured out from their 
cells, and to which insects stick. If a section of these glands be 
made and examined under the microscope, it will be seen to have 
an external layer of square cells, also filled with purplish fluid 
containing granular matter ; beneath this is another layer of cells, 
then a few much longer cells, and in the centre a mass of much 
larger cells, each containing a spiral fibre, which is continued down 
the foot-stalk to the leaf itself. These stalked glands have the 
power both of secreting the glutinous fluid above mentioned, and 
also of absorbing the matter which has been digested. Directly an 
insect has been caught, a curious change takes place in the interior 
of the cells of the hairs and glands; the protoplasm and granular 
matter therein contained, instead of being spread out evenly, 
collects together into masses, and remains thus until the process of 
digestion has been completed and the leaf re-expands. The pro- 
toplasm then gets again dissolved and distributed evenly through- 
