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The synapsis itself seems to have but a short existence: in 

 a longitudinal section through a head, where the anthers of the 

 innermost flowers have nuclei in the præsynaptic stage, there are 

 but few of the flowers, lying more toward the outside, which 

 show anthers in the synaptic stage. It often happens in the 

 synapsis stage, that the whole nucleus is pressed against the cell 

 wall, when it shoots forth projections through the wall. This 

 evidently depends upon the fixing fluid, and has already been 

 observed, for instance by Kör ni eke (31). 



Concerning the nucleolus I have made the following observa- 

 tion, which corresponds to what Hacker (4) has discovered in 

 animals; in the præsynaptic stage there are, as I have already 

 mentioned, usually two nucleoli, whilst in later stages only one 

 is to be found. Hacker considers this to have relation to the 

 gonomeric condition of the nucleus, and it is really remarkable, 

 that at the same time that the parent chromosomes unite, also the 

 nucleoli become one. The significance, this may have regarding 

 the relation of the nucleolus to the chromatin, is still difficult to 

 understand, but this phenomenon appears too often to be regarded 

 as a chance occurrence. 



The parallel threads become gradually more and more united 

 at the same time as the chromatin increases. The spirem stage 

 follows, when the chromatin threads appear rather thick and have 

 a ragged appearence. Thereupon a longitudinal split is to be 

 observed, that is to say the chromosomes once again begin to 

 separate from each other. The bivalent chromosomes at this period 

 appear to be quite isolated, and then a stage of shortening and 

 thickening (Diakinesis) enters. One can certainly discern, that the 

 original longitudinal split, which only appeared at the close of the 

 spirem stage, continues to remain distinct and even to increase. 

 The chromosomes are always double and their two halves are 

 twisted about each other several times. Finally the chromosomes 

 have attained their definite length inside the nucleus. They then 

 form rings, V's or short double segments, as often observed in 

 other plants at this stage. In H. auricula one can also easily 

 note, that the short double segments are really small chromosomes, 

 separated from each other, only being in connection at one end. 



In the diakinesis it is especially clear, that the 9 chromosomes 

 have different lengths and thus also different forms. 



The chromosomes are in proportion to the nucleus rather short, 



