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mantle fibres, and secondly, because in certain plants the 
chromosomes move along the fibres, and no contraction is 
observed ; moreover, he affirmed that fibres, although 
flexible, afford no evidence of the pushing force assumed by 
Meves. Dismissing Biitschli’s gelatin figures and Rhumbler’s 
model as inconclusive, he denied the validity of their theories 
on the grounds that they involve spindle formation between 
like poles, and based this argument upon the work of 
Vejdowsky and Mrazek, who showed that the action of 
osmosis, currents, and surface tension in the cell is the same 
at both centres. 
During the following year Gallardo put forward a modifica- 
tion of his earlier electric theory, based upon certain 
experiments of Lillie. The latter, after defining protoplasm 
as a complex aggregate of waterand colloid and ci’ystalloid sub- 
stances, showed that free nuclei and spermatozoids follow the 
negative current Avhen placed in a magnetic field ; whereas cells 
rich in cytoplasm tend to follow the positive. He accordingly 
assumed that chromatin and cytoplasm carry electric chai’ges 
of opposite signs, and pointed out that this assumption is 
consistent with their staining reactions. Gallardo thereupon 
assumed electric charges of opposite signs for the chromatin 
and cytoplasm in mitosis, and said that centrosomes move 
apart as a result of repulsion of like forces, while chromosome 
divergence is due to the combined effects of mutual repulsion 
and centrosome attraction. He explained cell division by 
assuming that the divergence of daughter-nuclei causes a 
fall of potential at the equator, thereby entailing in this 
region an increase of superficial tension and the formation of 
a zone of constriction. He accounted for the growth and 
fission of chromatin granules on the spireme by adopting 
Perrin’s theory of segmentation and divei’gence : each 
granule was said to grow under the favourable influence of 
superficial tension and cohesion until sufficiently large to be 
inducted with electric charges of like sign ; these act as an 
internal cause of dislocation, and by mutual repulsion effect 
fission of the granule, whose daughters undergo further 
