280 Jc Hs 8; MOORE: 
At first the chromosomes are attached to the centrosomes by 
a few faint protoplasmic strands, which are apparently of 
cytoplasmic origin ; but as time goes on the chromatin assumes 
a more and more equatorial position, and the linin filaments, 
being left stretched towards the centrosomes, help to form the 
central portion of an achromatic spindle figure, the equatorial 
moiety of which is nuclear, while its extreme ends appear to 
be cytoplasmic (figs. 17, 18, 19). 
8. A portion of the astral radiation round the centrosomes 
becomes connected with the outer ends of the chromatic rods, 
clothing the inner achromatic spindle with a sheath of cyto- 
plasmic fibres (m., fig. 19), structurally equivalent to Her- 
mann’s *‘ outer mantle.” 
9. The chromosomes to which these fibres are attached 
assume the form of short bent rods, and lie (fig. 19) at all 
angles on the equatorial plane, being by no means specially 
related to the surface of the spindle figure, and in surface view 
they consequently present the appearance of a somewhat 
irregular chromatic disc (fig. 21). 
10. The achromatic spindle would thus appear to have a 
dual origin, its superficial portion and extreme ends originating 
in the cytoplasm, while its greater internal and equatorial 
mass arises from the nucleus—a state of things approximately 
coinciding with Flemming’s! views respecting its complex 
origin in Amphibia, as opposed to the general acceptation of 
its wholly cytoplasmic nature among plants. 
11. When the equatorial plate is fully formed, the chromo- 
somes, after becoming extremely broad and flat, split longi- 
tudinally down the middle, each into two daughter-threads, 
which gradually separate from one another towards the 
spindle-poles (figs. 19, 20, 22, 23). During their transit 
those daughter-elements, which were at first internal, work 
outwards to the surface of the spindle in such a way that by 
the time they are halfway from the equator to the poles, the 
chromosomes of each daughter-nucleus have assumed the 
1 “Neue Beitrage zur Kenntniss der Zelle,” ii Theil., ‘Arch. fiir mikr, 
Anat.,’ Bd, xxix, p. 389. 
