which produced this effect, for I subsequently ascertained that it is
quite powerless. I also procured some extract of hyoscyamus from three
shops, and made infusions of the same strength as before. Of these
three infusions, only one acted on some of the leaves, which were
tried. Though druggists believe that all the albumen is precipitated in
the preparation of these drugs, I cannot doubt that some is
occasionally retained; and a trace would be sufficient to excite the
more sensitive leaves of Drosera. [page 85]
CHAPTER VI.
THE DIGESTIVE POWER OF THE SECRETION OF DROSERA.
The secretion rendered acid by the direct and indirect excitement of
the glands Nature of the acid Digestible substances Albumen, its
digestion arrested by alkalies, recommences by the addition of an
acid Meat Fibrin Syntonin Areolar tissue Cartilage Fibro-cartilage
Bone Enamel and dentine Phosphate of lime Fibrous basis of
bone Gelatine Chondrin Milk, casein and
cheese Gluten Legumin Pollen Globulin Haematin Indigestible
substances Epidermic productions Fibro-elastic
tissue Mucin Pepsin Urea Chitine Cellulose Gun-cotton Chlorophyll Fat
and oil Starch Action of the secretion on living seeds Summary and
concluding remarks.
As we have seen that nitrogenous fluids act very differently on the
leaves of Drosera from non-nitrogenous fluids, and as the leaves remain
clasped for a much longer time over various organic bodies than over
inorganic bodies, such as bits of glass, cinder, wood, &c., it becomes
an interesting inquiry, whether they can only absorb matter already in
solution, or render it soluble, that is, have the power of digestion.
We shall immediately see that they certainly have this power, and that
they act on albuminous compounds in exactly the same manner as does the
gastric juice of mammals; the digested matter being afterwards
absorbed. This fact, which will be clearly proved, is a wonderful one
in the physiology of plants. I must here state that I have been aided
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