Because, by breaking the stem, we rupture the vessels of the plant, and cause the nutritive fluid to escape. The sap of the plant is analogous to the blood of man, and the vessels, to the arteries and veins of the animal body.
1156. Why, if we split the petal of a tulip, do we see cells containing matter of various colours?
Because, by splitting the petal of the flower, we disclose the anatomy of its structure, and bring to view those cells, or organs, of the vegetable body, by which the different colouring matters are secreted.
1157. Why, if we break a pea-shell across, do we discover a transparent membrane which may be removed from the green cells underneath?
Because we separate from the cellular, or fleshy part of the shell, the membrane, which forms the epidermis, and answers to the skin of the animal body.
1158. Why, if we cut through a cabbage stump, do we find an outer coat of woody fibre, and an inner substance of cellular matter?
Because the woody fibre forms a kind of skeleton, which supports the internal stricture of the plant, and gives form and character to its organisation. The woody fibre of plants is analogous to the bony structure of animal bodies.
1159. Why, if we cut across the stem of a plant do we see numerous tubes arranged in parallel lines?
Because we thereby bring to view the vessels formed by the membranes and fibres of the vegetable body, for the transmission of the fluids, by which the structure is sustained.