224 THE MICROSCOPICAL NEWS. 
hairs, which project upwards and outwards from the opening. It 
is supposed that their office is to protect the orifice, and thus 
prevent insects of too large a size from attempting to pass through. 
Still nearer the free border of the valve are five or six glandular 
hairs with very large knobs, placed on very short footstalks. The 
mouth of the bladder is very stiff and of a hard structure, and from 
it arise numerous delicate glandular hairs looking inwards, whilst 
there are several tentacles projecting from and extending outwards. 
On the surface of the bladders are numerous glands, the uses of 
which are not known; the same kind of glands are also found 
about the leaves and stems of the plant. All these glands and 
glandular hairs are better seen and rendered much more distinct if 
a little carmine is added to the water, when they instantly take a pink 
colour ; the hairs in the diagram have been coloured to make them 
more easily visible. The internal structure of the bladder is most in- 
teresting. If a longitudinal section of one is made and examined 
under the microscope, it will be seen to be covered with innumerable 
hair-like projections. These are situated at the corners of the cells, 
and are quadrifid, that is to say, that from a common centre arises 
four hairs, two of which are long and two short. The two larger 
projections are directed upwards, and the two shorter towards the 
valve. The diagram represents some of these quadrifid processes 
situated at the end of a long cell. These hairs contain protoplasm 
in constant motion, and no doubt take the place of the roots of the 
plant, which are entirely absent. Each process also contains a 
large nucleus, which continually changes its shape. They absorb 
the contents of the bladders, which are destined to nourish the 
plant. Mr. Darwin thinks that no true digestion takes place within 
the bladders, as there are no glands present to secrete a gastric 
fluid; but that each insect caught decomposes, and thus each 
bladder, as it were, forms its own liquid manure, which the quad- 
rifid process absorb. There is no doubt, then, but that the use of 
the bladders is to catch insects, and as many as from twelve to 
twenty of these can be counted at once in a bladder in various 
stages of decomposition, the last one entrapped perhaps being still 
alive and active. It is a disputed point whether insects force their 
way through the valve into the bladder, or whether the valve is or 
is not endowed with a certain amount of irritability, and that when 
touched it flies back and draws in the insect. . . . During the 
last fortnight, having obtained some plants from Burnham Beeches, 
I have been much interested in carrying out a few experiments, and 
have come to the conclusion that no creature small enough to enter 
by the neck of the bladder could of itself open the valve if the 
plant be freshly obtained and is in a healthy state. I tried to pass 
hairs, bristles, and even fine needles through, but could not succeed 
until the plants had become, as it were, weakened from being kept 
