332 
MONTGOMERY. 
[Vol. XV. 
Ruckert (’ 92 ) studied the maturation of the eggs of Scyllium , 
Pristiurus , and Torpedo. In young germinal vesicles there 
are a few small nucleoli, most of them peripheral in 
position. In larger ova they have increased in number and 
size, and become grouped in a cluster at that part of the nucleus 
which is nearest the animal pole of the egg ; this cluster may 
occupy one-fourth of the whole space of the nucleus. Later, 
but still antecedent to the formation of the pole spindles, the 
nucleoli decrease in size and commence to stain very faintly. 
Ruckert considers the nucleolus of an egg cell as strictly com¬ 
parable to that of any somatic cell. From the fact that the 
nucleoli are largest, and color most intensely, at the same time 
that the chromosomes do, and simultaneously with the latter 
become gradually invisible later, he concludes : “dass es die 
Stoffwechselvorgange der Chromosomen sind, zu welchen die 
Nucleolen in direkter Beziehung stehen, sei es nun, dass sie 
notwendige Stoffe an die letzteren abgeben (vielleicht das Chro¬ 
matin, wie schon Flemming vermutete), oder dass sie Stoffe 
von ihnen aufnehmen, Oder endlich dass beides zugleich der 
Fall ist. . . . Spater freilich, wenn die. Chromosomen merklich 
an Substanz verlieren, wird man eher geneigt sein, die betref- 
fenden Nucleolen als Trager von Zerfallsprodukten der Chromo¬ 
somen anzusehen.” He also observed that the number of the 
nucleoli varies in different germinal vesicles of the same age, 
that a number may coalesce to form a larger one, and that a 
few wander out into the cytoplasm, where they become paler 
and finally vanish. 
Wiren (’ 92 ) found that the smallest germinal vesicles of Chae- 
toderma contain no nucleoli; in nuclei of about 15ft diameter a 
nucleolus appears for the first time, and consists of a dense 
mass of granules, which stain differently from the other nuclear 
granules. More than one nucleolus is never to be found. 
1893. 
Van Bambeke (’ 93 ) found one to five homogeneous nucleoli 
in the germinal vesicles of Scorpaena scrofa , and notes that in 
older eggs they do not stain as deeply with carmine as in 
younger ones. 
