Footnote 86: "Entw. d. Geryonideneies." _Jenaische Zeitschrift_, Bd. VII.
Footnote 88: _Organologische Studien_, Zweites Heft.
Footnote 89: "Beiträge z. Entwicklungsgeschichte der Knochenfischen." _Zeit. für Wiss. Zoologie_. Bd. XXII. 1872.
These figures[90] are possibly due to the streaming out of the protoplasm of the nucleus into that of the cell[91]. The appearance of striation may on this hypothesis be explained as due to the presence of granules in the protoplasm. When the streaming out of the protoplasm of a nucleus into that of a cell takes place, any large granule which cannot be moved by the stream will leave behind it a slack area where there is no movement of the fluid. Any granules which are carried into this area will remain there, and by the continuation of a process of this kind a row of granules may be formed, and a series of such rows would produce an appearance of striation. In many cases, _e.g._ Anodon, vide Flemming[92], even the larger yolk-spherules are arranged in this fashion.
Footnote 90: The memoirs of Auerbach and Strasburger (_Zellbildung u. Zelltheilung_) have unfortunately come into my hands too late for me to take advantage of them. Especially in the magnificent monograph of Strasburger I find drawings precisely resembling those from my specimens already in the hands of the engraver. Strasburger comes to the conclusion from his investigations that the modified nucleus always divides and never vanishes as is usually stated. If his views on this point are correct part of the hypothesis I have suggested above is rendered unnecessary. The striæ of the protoplasm, which in accordance with Auerbach's view I have considered as being due to a streaming out of the matter of the nucleus, he regards as resulting from a polarity of the particles in the cell and the attraction of the nucleus. My own investigations though, as far as they go, quite in accordance with those of Strasburger, do not supply any grounds for deciding on the meaning of these striæ; and in some respects they support Strasburger's views against those of other observers, since they demonstrate that in Elasmobranchii the modified nucleus does actually divide.
Footnote 91: This is the view which has been taken by Auerbach (_Organologische Studien_).