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Cells, again, preside over the chemical processes which elaborate the living fluids; they change their form to become the agents of voluntary and involuntary motion; the soul itself sits on a throne of nucleated cells, and flashes its mandates through skeins of glassy filaments which once were simple chains of vesicles.
The large nucleated ganglionic cells in this system contain a very large proportion of etheric matter, and are hence more easily affected by the coarser astral vibrations than are the cells in which the proportion is less.
The word cell received a final definition as "a small mass of protoplasm supplied with a nucleus." In this widened and culminating general view of the cell theory it became clear that every animate organism, animal or vegetable, is but a cluster of nucleated cells, all of which, in each individual case, are the direct descendants of a single primordial cell of the ovum.
No chemical synthesis could put into the cell, apparently nothing more than a simple clot of nucleated protoplasm, that activity sine matter, that potential vital force, that mysterious factor which causes a cell to develop into man. And the elusive attention of children would seem to tell us that the psychical man is subject to analogous laws of auto-creation.
But, as it is admittedly impossible to draw any distinct boundary line between this no man's land and the vegetable world, on the one hand, or the animal, on the other, it appears to me that this proceeding merely doubles the difficulty which, before, was single. Protoplasm, simple or nucleated, is the formal basis of all life.
Traced back to its earliest state, the nettle arises as the man does, in a particle of nucleated protoplasm. And in the lowest plants, as in the lowest animals, a single mass of such protoplasm may constitute the whole plant, or the protoplasm may exist without a nucleus.
Each, starting from the condition of a simple nucleated cell, becomes a cell-aggregate; and this passes through a condition which represents the gastrula stage, before taking on the features distinctive of the group to which it belongs. Stated in this form, the "gastraea theory" of Haeckel appears to the present writer to be one of most important and best founded of recent generalisations.
From this and other such cases I am led to suspect that the calciferous cells are developed from the larger nucleated ones; but how this was effected was not ascertained. When an anterior gland contains several minute concretions, some of these are generally angular or crystalline in outline, while the greater number are rounded with an irregular mulberry-like surface.
If the body be studied in its development, it is found to originate from a single mass of nucleated protoplasm, a single cell with a nucleus and nucleolus. From this original cell, by growth and development, the body, with all its various tissues, is built up. Many fully formed organs, like the liver, consist chiefly of cells.
Under the microscope cartilage is seen to consist of a matrix, or base, in which nucleated cells abound, either singly or in groups. It has sometimes a fine ground-glass appearance, when the cartilage is spoken of as hyaline. In other cases the matrix is almost replaced by white fibrous tissue.
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