468 
MONTGOMERY. 
[Vol. XV. 
within the nucleus would show that dissolution commences 
in the nucleus; and we must assume that when the nuclear 
membrane has disappeared the cytoplasmic substances which 
then come into contact with the nucleolus would cause its 
rapid and total dissolution. It may be remarked that in the 
region of the fully formed spindle (Fig. 311) no trace of the 
red-stained nuclear sap is longer to be seen; accordingly this 
sap with its contained nucleolar substance must either have 
been distributed through the cytoplasm or have been chem¬ 
ically changed by that portion of the latter which immediately 
surrounds the spindle. 
In the ovary no ova are to be found which have advanced 
beyond the production of the first pole body, so that the forma¬ 
tion of the second pole body must occur after the egg has been 
discharged from the ovary; I had no material at hand to enable 
me to determine the relation of the nucleolar substance in the 
female pronucleus. 
Of considerable morphological interest are the metamor¬ 
phoses of the chromatin in the various ovarial stages. In those 
small ovogonic mitoses (Fig. 300) from which the true egg cells 
(first ovocytes) are derived aster and dyaster stages are to be 
found ; with the lens used for this study (the homogeneous 
immersion ^ of Zeiss) I could not determine the form of the 
chromosomes. As the ovum increases in size the dense chro¬ 
matin mass of the aster gradually loosens, until up to the time 
when the nuclear sap commences to stain red (Figs. 301-304) 
the chromatin is arranged in the form of rather numerous 
granules, which are situated mostly close to the nuclear mem¬ 
brane. Thus far the chromatin has stained intensely blue, with 
the double stain haematoxylin and eosin ; but when the nuclear 
sap begins to stain with eosin a marked change takes place in 
the character and arrangement of the chromatin; it now stains 
a lilac color, often more reddish than bluish, and has no longer 
a peripheral position, but becomes arranged in the form of 
threads, sometimes in the form of a small number of loops, the 
two ends of each loop being joined together (Figs. 304, 305, 
307) 3°9)- In some of the larger germinal vesicles absolutely 
no trace of chromatin can be found (Fig. 316). In the equator 
