. The cell; outlines of general anatomy and physiology. Cells; Anatomy; Physiology; Cells; Anatomy; Physiology. THE VITAL PHENOMENA OF THE CELL 245. Fig. 134. — Two nuclear spindles from the yolk of the germinal disc of a Trout's egg: the centrosome is exerting a disturbing influence upon the arrangement and distribution of the daughter-segments of the second spindle. (After Hennegu\.) the same category. It is well known, that a large number of nuclei (merocytes) are scattered throughout the yolk layer; this is situated below the germinating cells in eggs, which are partially segmented by furr
. The cell; outlines of general anatomy and physiology. Cells; Anatomy; Physiology; Cells; Anatomy; Physiology. THE VITAL PHENOMENA OF THE CELL 245. Fig. 134. — Two nuclear spindles from the yolk of the germinal disc of a Trout's egg: the centrosome is exerting a disturbing influence upon the arrangement and distribution of the daughter-segments of the second spindle. (After Hennegu\.) the same category. It is well known, that a large number of nuclei (merocytes) are scattered throughout the yolk layer; this is situated below the germinating cells in eggs, which are partially segmented by furrows. Occasionally some of them collect to- gether to form small spindle aggregations, whilst at the same time they are making preparations for division. Hence it is very instructive to see, that in the following case, de- scribed by Henneguy (Fig. 134), the centrosomes act as attraction centres. Two me- rocytes, which are in the act of dividing, lie close together in the common mass of yolk, so that the longitudinal axis of spindle B would, if pro- duced, cut spindle A in its equator ; we see also that the one centrosome h is very near to spindle A. In con- sequence, the arrangement of the daughter-segments of spindle A has been, disturbed to a considerable extent. Instead of their being arranged in two groups near the centrosomes, a, a, as would occur normally, a number of those which are within the attraction sphere of the centrosome h of the neighbouring foreign spindle have been drawn towards it. In a word : the centrosome of the one spindle has evidently exerted a disturbing influence upon the arrangement and distribution of the daughter-segments of the other spindle. Henneguy has observed triasters, such as the one depicted in Fig. 135, and also tetrasters, in the germinal cells of the same object; these gradually separated themselves from the layer of merocytes. At the close of this fourth section we may mention the degeneration processes, which sometimes occur in cell
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