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MONTGOMERY. 
[Vol. XV. 
6 . Amoeboid Movements, Divisions, Fusions of Nucleoli. 
Amoeboid movements have been seen in life in metazoan 
cells by the following observers (germinal vesicles): A. Brandt 
(’74, Blatta), Eimer (’75, Silurus), O. Hertwig (’76, Rana, 
Pterotrachea ), La Valette St. George (’66, Libella; ’83, Isopoda ), 
Bergh (’79, Gonothryaea), Van Beneden (’69, ’76, Polystomum, 
Rana), Balbiani (’64, several genera of spiders), Leydig (’83, 
Libella), A. Brandt (’78, numerous Insecta, Distomum) f Van 
Bambeke (’86, Blatta), Knappe (’86, Bufo), Auerbach (’74a, 
Teleostii). In somatic cells : Schwalbe (’76, sympathetic gan¬ 
glion cells of Rana), Kidd (’75, epithelial cells from the mouth 
of Rana), Hodge (’94, nerve cells of Rana), Auerbach (’74b, 
salivary gland cells of Musca). In Protozoa: Van Beneden 
(’69, ’76, Gregarina, Monocystis). In plants, Zacharias (’85) has 
observed amoeboid movements in the nucleoli of Chara (an 
observation overlooked by Zimmermann, who states that such 
movements have not been seen in plants). 
These observations would show that amoeboid movements 
are probably natural phenomena of certain nucleoli, but one 
should not be too positive of the naturalness of these phe¬ 
nomena, since some of the observations were made upon the 
heated stage, and in all of them the object was probably more 
or less compressed and placed in artificial conditions. But they 
are in all probability frequently normal phenomena, since, as we 
shall see, divisions and fusions of nucleoli are certainly normal 
and of wide occurrence, and the latter can only be classed as 
forms of amoeboid motion. The question arises, Are these 
movements wholly passive, caused by movements in the other 
parts of the nucleus, or should they be considered an inherent 
function of the nucleolus ? The latter alternative would seem 
the more probable, since no movements of the other nuclear 
elements are known in the resting cell. Van Beneden (’69) has 
described rhythmic expansion and contraction of the volume of 
nucleoli in gregarines. But all these movements of nucleoli 
should not be regarded as automatic motions of the nucleolus 
in the sense that an Amoeba forms and retracts processes ; but 
rather with Rhumbler (’ 93 ) they should be regarded as “ Auf- 
