They are prominent during cell-division, but many disappear in.
The increasing temperature raises the rate of animal metabolism, while the higher alkalinity is a stimulus to cell-division.
The centrosomes which play so important a part in cell division may be found either lying within or at one side of the nucleus in the vegetative condition of the cell.
In pathological cell-division it happens occasionally that the segmentation of the cytoplasm is delayed beyond that of the mitotic network.
Contrary, however, to the experience of others, he has never found that the attraction-spheres play an important part in direct cell-division, or, indeed, that they exert any influence whatever upon the mechanism of the process.