The last of the organs of plants is the flower, or blossom, which produces the fruits and seed. These may be considered as the ultimate purpose of nature in the vegetable creation. From fruits and seeds animals derive both a plentiful source of immediate nourishment, and an ample provision for the reproduction of the same means of subsistence.
The seed which forms the final product of mature plants, we have already examined as constituting the first rudiments of future vegetation.
These are the principal organs of vegetation, by means of which the several chemical processes which are carried on during the life of the plant are performed.
EMILY.
But how are the several principles which enter into the composition of vegetables so combined by the organs of the plant as to be converted into vegetable matter?
MRS. B.
By chemical processes, no doubt; but the apparatus in which they are performed is so extremely minute as completely to elude our examination. We can form an opinion, therefore, only by the result of these operations. The sap is evidently composed of water, absorbed by the roots, and holding in solution the various principles which it derives from the soil. From the roots the sap ascends through the tubes of the alburnum into the stem, and thence branches out to every extremity of the plant. Together with the sap circulates a certain quantity of carbonic acid, which is gradually disengaged from the former by the internal heat of the plant.
CAROLINE.
What! have vegetables a peculiar heat, analogous to animal heat?
MRS. B.