MONTGOMERY. 
[Vol. XV. 
5H 
a somewhat similar method of formation of the smaller nucleoli 
of Gregarina blattuvum. Now I found in the nucleus of the 
gregarine from Lmcus numerous nucleoli of different dimen¬ 
sions, and often irregular in their outlines ; and this irregularity 
in form would point not only to amoeboid movements of the 
nucleoli, but also to nucleolar divisions, since in the largest 
nuclei we find a large number of small nucleoli. All appear¬ 
ances showed that these smaller nucleoli are division products 
of the larger ones ; but it seems that they simply bud off from 
the surface of the latter, and are not preformed in their interior. 
In other words, Schneider and Marshall are probably correct 
in concluding that the smaller nucleoli are disassociated portions 
of the larger ones ; but they may perhaps be mistaken in 
assuming that they are preformed in the interior of the latter, 
since these investigators may have mistaken vacuoles for intra- 
nucleolar nucleoli. (Other observations on nucleolar divisions 
in resting cells : Hermann, ’89 ; Vejdovsky, ’95a ; Biitschli, ’80; 
R. Hertwig, ’76 ; Kultschitzky, ’88 ; Bergh, ’79 ; Bannwarth, ’92 ; 
Stuhlmann, ’86 ; A. Brandt, ’78 ; Scharff, ’88 ; Eisig, ’87 ; 
Cunningham, ’95 ; Kosinski, ’87, ’93 ; Carnoy and Lebrun, ’97a ; 
Steinhaus, ’88 ; Cuenot, ’91 ; Metzner, ’94.) 
Fusions of nucleoli are not as widely known as divisions, but 
there are some facts which would show that the former processes 
are by no means unusual in their occurrence. Such fusions 
have been described for cells of plants by Zacharias (’85), Mann 
(’92), and Wager (’93) ; for animal cells by Rhumbler (’93, ’95), 
Brauer (’9l), Leydig (’ 50 ), Pfitzner (’83), and Riickert (’92). I 
have found fusions of the nucleoli to be characteristic phenomena 
of certain stages in the maturation of the germinal vesicles of 
nemerteans, an extreme case being furnished by Stichostemma , 
where sometimes all the nucleoli may fuse together at the 
center of the nucleus, and so produce a single large one. The 
nucleolus at the time of its origin may be said to be undergoing 
a process of fusion, since it is produced by the coalescence of 
numerous smaller portions of nucleolar substance. There is 
nothing problematical in regard to the fusion of nucleoli, since 
it is a physical property for bodies of like nature (when fluid) 
to fuse together when they come into contact, though this 
