There is a horizontal division across the whole egg-cell, and the nuclei are now four, two above, and two below.

But those below retain their original nature, those above are new in nature.

And those above correspond again to those below.
In the developed child, the great horizontal division of the egg-cell, resulting in four nuclei, this remains the same.

The horizontal division-wall is the diaphragm.

The two upper nuclei are the two great nerve-centers, the cardiac plexus and the thoracic ganglion.