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Also for the nuclei of the integuments and nueellus of Fritillaria and 
of the ovules of Tudipa the same results were obtained. 
Concerning the individuality of the chromosomes van WisseLINGH 
has shown that it exists in the spirema, since at that stage a 
continuous thread is never found. But his further observations as well 
as those of GRÉGOIRE and WyGarrts indicate that probably, even in the 
resting stage, this individuality never entirely disappears. Mr. SypKuns 
was led to the same conviction by his observations about the 
formation of the spireme and of daughter-nuclei from the daughter- 
spiremes. He speaks of a “centralisation and decentralisation of a 
number of chromatine masses, which in certain stages form as 
many chromosomes.” 
About the behaviour of the chromosomes during the process of 
division little that was new could be found in this investigation for 
the reason mentioned. The number of chromosomes was fixed at 
about 60, but in certain nuclei it decidedly is much smaller. Neither 
is the shape of the chromosomes constant; in the same nucleus U- 
shaped, as well as W- and J-shaped ones could be found. 
The study of the nuclear spindle on the other hand gave important 
results, not so much about the formation of the spindle as about its 
further history and the part played by it in cellular division. 
The formation of the spindle could be followed in details. Round 
the free nuclei in the parietal layer of protoplasm of the embryo-sac 
granular protoplasm occurs with many very small adventitious vacuoles ; 
round the nuclei of the first endosperm-cells also protoplasm with 
several small vacuoles. Now, when the nuclei begin to divide and the 
nuclear membranes are dissolved, the surrounding protoplasm pene- 
trates into the nuclear space, at first without many vacuoles, and forms 
at the interior the spindle-threads, which at first consist of coherent 
granules and later become smoother. They gradually assume parallel 
directions and are connected to a bundle without strongly converging 
towards its poles. The nuclei are then in the spireme-stage. Later, in 
the aster-stage, besides the threads already mentioned, others are 
formed in exactly the same way, which grow thicker and only 
proceed from the poles to the equator, where they are attached to 
the chromosomes, which have been formed in the mean time. They 
are found not only at the circumference of the spindle, but also in 
the interior part of all the longitudinal sections of a nucleus. Srras- 
BURGER has called the former sort of threads, running from pole to 
pole, “Stiitzfasern”, the shorter and thicker ones “Zugtasern”. 
Now metakinesis follows and in the dyaster-stage a separation 
of the two sorts of spindle-threads has taken place. The shorter 
