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documents dont il est question dans la présente note. 
C’est pour mettre en relief ce dernier point que nous 
avons cru devoir publier une série de lettres du savant 
et regretté professeur de Liège. 
Au reste, nos conclusions sont parfaitement d’accord 
avec celles d’un auteur, estimable entre tous, qui s est 
donné à cœur d’écrire une très judicieuse et très conscien¬ 
cieuse biographie de Éd. Van Beneden ; nous avons 
nommé A. Sedgwick (Nature, 19 mai 1910). JNous cite¬ 
rons le paragraphe tout entier dans lequel l’auteur 
anglais parle de la découverte de la sphère attractive par 
Éd. Van Beneden. 
« By his use of Ascaris megalocephala as the material 
of his investigation, he introduced a means of research 
which, in his own hands and those of his followers, led 
to the most important results. He was the lirst to show, 
for the ovum, that the chromatic threads are a portion 
of the nelwork existing in the nucléus. He laid spécial 
stress upon the fact that the two daughter chromosomes 
were alike to the smallest detail, and he lirst pointed 
out that they pass to opposite pôles of the spindle. He 
discovered the corpuscule central in 1876 (lirst seen, it 
is true, by Flemming in 1875), and lirst demonstrated 
its importance in cell division. He was also the lirst to 
show that it is in many cases, if not in ail, a permanent 
organ of the cell (1885 and 1887). He also discovered 
the sphère attractive. Bolh these structures later received 
other names, the former heing known as centrosome 
and the latler as centrosphère ; but whatever naines be 
applied to them — a matter of no importance — the fact 
remains that they were discovered, and their importance 
appreciated by van Beneden. » 
