314 BULLETIN OF THE 



nuclei were still almost unchanged (see also op. cit., p. 108, Fig. 29 B. n). 

 The author thinks he has seen, on sections of an egg presenting the 

 first traces of the [first or] transverse furrow, the disappearing nucleus 

 in the shape of a pale, hardly visible body midway between the two stars. 

 It is described as an elongated, roundish, clear space, which differs only 

 very slightly in its optical properties from the surrounding protoplasm, 

 and is especially distinguishable only by the fact that the rays of the 

 two stars which traverse it are interrupted at its boundaries. The lim- 

 its of this space are thus clearly indicated by granules somewhat larger 

 than those which compose the rays (Fig. 24). 



It is with reluctance that one ventures to impeach the accuracy of 

 another's observations, especially if the observer is one of such broad 

 experience as Bobretzky ; and yet I am convinced that his " disappear- 

 ing nucleus " is in reality nothing more or less than the " nuclear disk " 

 seen obliquely, — not edgewise, as in Fig. 23. The means of settling the 

 question lay of course in the hands of the observer, for the two sides of 

 the oval body could not have occupied the same niveau, if my interpreta- 

 tion is correct, and I confess it seems difficult to understand how this 

 could have been overlooked by so competent an observer. It becomes 

 all the more difficult to understand when, further on,* Bobretzky says 

 that possibly the refractive granules surrounding the nucleus may be 

 coordinated with the transverse granular band seen in the preceding 

 figure. That the two are really the same structures, I have not the least 

 doubt ; but the author's attempt to explain their relation to each other 

 cannot be regarded as successful. It is in accordance with an erroneous 

 view of the origin of the median zone that he would interpret the mean- 

 ing of this figure in case he is compelled to grant that its surface gran- 

 ules are identical with those of the transverse granular band. In that 

 event, he says, one would be justified in drawing the conclusion that — 

 in direct opposition to Biitschli's view — the granular zone (Fig. 23) is 

 formed out of two rows of granules, which approach each other and unite 

 in the middle of the [in the mean time] dissolved nucleus. That such 

 an approach of granules takes place is based on the assumption that the 

 egg drawn in Fig. 24 is less advanced (younger) than that drawn in Fig. 

 23, for a direct observation of the approach is not claimed. This as- 



*".... vielleicht ware es moglich, die an den Grenzen des Kernes befindlichen 

 glanzenden Korner mit dem queren Kornerstreifen der vorigen Figur gleichzustellen, 

 woraus man den Schluss ziehen aiirfte, dass die aequatoriale Kornerzone sich, der 

 Meinung Biitschli's ganz entgegengesetzt, aus zwei, sich einander nahernden und in 

 der Mitte des aufgelbsten Kerns zusammentretenden Kbrnerreihen bildete." (p. 100.) 



