344 
MONTGOMERY. 
[Vol. XV. 
1894 . 
Blochmann (’94) gives a preliminary account of the results 
of the observations of Keuten (’95). 
Born (’94) investigated the maturation of the ovum of Triton. 
In the “ Urei ” are one or several large, spherical nucleoli. In 
the second stadium of the maturation (production and degenera¬ 
tion of a “ Chromatinfadenknauel ”) there are at first ten nucle¬ 
oli, then they become more numerous, increase in size, and 
lie close to the nuclear membrane. In the third stadium (eggs 
of from 200ft to 350ft in diameter) the nucleoli increase still 
more in size. In the fourth stadium (eggs measuring from 350ft 
to 800ft, first appearance of yolk in the cytoplasm) most of the 
nucleoli lie in the peripheral “ Karyohyaloplasma,” only a few 
pale ones being in the center of the nucleus (this part of the 
nucleus he terms “ Centralkorper ”). At the commencement 
of this stage the nucleoli increase, at its conclusion decrease, 
in number, and “wahrend der ganzen Periode steigt die Zahl 
der verkleinerten und abgeblassten Nucleolen im Centralkor¬ 
per,” only a few of these pale ones being situated at the 
periphery of the nucleus. Thus while at the beginning of this 
period the nucleoli attain their maximum size, at its end most 
of them wander towards the center of the germinal vesicle, 
become smaller, and lose their staining power. Fifth stadium 
(the nucleus passes to the periphery of the egg): the nucleoli 
decrease still further in size, and continue to wander to the 
center of the nucleus ; some of the larger ones contain vacuoles, 
and for the first time appear granular ; the smaller, lightly 
staining nucleoli are division products of the larger ones. At 
the commencement of the sixth stadium (formation of the first 
pole spindle) all the nucleoli lie in irregular rows around 
the “ Centralkorper,” stain quite intensely, and are regularly 
vacuolated ; the few in the midst of the “ Centralkorper ” are 
smaller and stain more faintly ; when the nucleus has decreased 
still further in size, all the nucleoli vanish at once. Born con¬ 
cludes as follows : “ Eine sichere Herleitung der peripheren 
Nucleolen von den Nucleolen des Ureies, bin ich freilich nicht 
im Stande zu geben. . . . Die Nucleolen stehen in Beziehung 
