Fig. 24. A very young leaf of Crassula portulaca, the five cells which solely compose it being still surrounded by a parent-cell.
25. Three cells from an articulated hair of potato, with a retiform current of mucus upon their walls. the central cell the direction of the currents is partially indicated by arrows.
In all the instances in which I have observed the movements in the cells of phænogamous plants, I have constantly found the moving matter to consist of a yellowish mucous fluid, perfectly insoluble in distilled water, and mixed with minute black granules, but differing entirely from the other aqueous sap of the cells; and even when the currents were so small as to appear merely as excessively minute delicate lines of black points, I succeeded with higher magnifying powers in distinguishing the yellowish mucous fluid, especially when aided by the favorable circumstance (which not unfrequently occurs) of the current becoming arrested by some impediment, which causes a somewhat larger quantity of the moving material to accumulate, and is generally followed either by a change in the direction, or a division of the current.
PLATE II.
Fig. 1. Cells from the epidermis of the pericarp of Ocymum basilicum, moistened with water, so that the mucous globule has expanded, and torn the outer cell-wall (a) from the side walls (b).
2. Cells from the pericarp of the epidermis of Ziziphora dasyantha.
3. Cells from the pericarp of the epidermis of Salvia verticillata.
4. Cells from the pericarp of the epidermis of Salvia Horminum.
5. Cells from the pericarp of the epidermis of Salvia Spielmanni.
2, 3, 4 and 5, a, exhibit the remains of the side-walls of the ruptured cells.
6. A portion of the epidermis (a) and of the integument (b) of the ovule of Collomia coccinea. The epidermis-cells contain merely granules of starch.
