EMBRYOLOGY OF CIEPSINE. 229 



termed Kernplatte by Strasburger ; and in these cases the appear- 

 ance is of so doubtful a character that I have omitted it in my 

 drawings. Some authors have hiid great stress on the inter- 

 stellate lines, especially Biitschli. In many of Strasburger^s 

 figures also the two poles with their radial lines are entirely 

 wanting, while the spindle-fibres with their equatorial nuclear 

 plate is very prominent. On the other hand, Fol, who was the 

 first to describe these phenomena with any degree of accuracy, 

 in his well-known paper on the development of Geryonia (ttV)' 

 lays particular stress on the star-shaped poles. He maintains 

 (wTTT-ii") that the spindle-fibres are identical with the stellate 

 rays and that their difference in appearance is due to the fact 

 that they are in different mecha. 



Bobretzky (^-fr), who studied these phenomena in the egg of 

 Nassa came to the same conclusion as Fol. My preparations 

 seem to confirm this view. Whether this interpretation can be 

 reconciled with the investigations of Butschli, O. Hertwig, and 

 Strasburger, remains to be seen. 



The entire amphiaster reminds one, as Fol (4W) ^^^d Stras- 

 burger (i^) have already observed, of the picture of iron-dust 

 arranged about the poles of a magnet. This resemblance was 

 at once remarked by Leuckart and others who have seen my 

 preparations. The interstellate lines often appear curved, but 

 no one has yet observed any curves in the radial lines not in- 

 cluded within the spindle, which we should expect to see if this 

 radial phenomenon were of a magnetic nature. It is not impos- 

 sible that such curves do exist, and that they are so inconspicuous 

 that they have been overlooked. Thus far these figures have 

 been studied for the most part in microscopic preparations. If 

 the stellate lines are curved in the living condition, this feature 

 might be obscured or entirely obliterated by reagents. No satis- 

 factory explanation of these radial appearances have yet been 

 given. According to the karyolytic interpretation of Auerbach 

 (a-o-o-T^T)> t-hey are produced by innumerable fine streams of 

 nuclear fluid from the ends of the spindle. Butschli (-nrl^-). 

 refers them to a reciprocal action between the fluid of the pohir 

 areas ("Ceiitralhof ") and the surrounding protoplasm — '' optis- 

 cher Ausdruck eiuer von dem Centralhof ausgehende physika- 

 lisch-chemischen Anderung des Plasmas.^' 



Gotte (-g-yLVs) manitains that a process of endosinosis begins 

 as soon as the egg comes in contact with water (Unke), and 

 that the radial arrangement is only the optical expression of the 

 process of difl'usion. These explanations, as will be seen later, 

 do not account for some very important features of nucleus- 

 action. 



Flemming {-^j^--^) refers them to a structural relation of 



