226 A TEXTBOOK OF GENERAL BOTANY 
membrane disappears, and the fibers grow into the nucleus. 
Some of them become connected with the chromosomes, while 
others stretch from pole to pole. At this stage the whole col- 
lection of fibers assumes the shape of a spindle, and collectively 
they are called the spindle (Fig. 229, F). 
After the growth of the spindle fibers into the nucleus and 
the disappearance of the nuclear membrane the karyolymph 
becomes mixed with the surrounding cytoplasm. As both nuclear 
membrane and karyolymph disappear and become mixed with 
the cytoplasm, and do not form part of the daughter nuclei, 
they cannot be regarded as permanent cell organs. During the 
early stages of prophase the nucleolus usually becomes steadily 
smaller and may disappear altogether, indicating that it consti- 
tutes a store of reserve material which is drawn on during the 
process of division. If the nucleolus persists after the disap- 
pearance of the nuclear membrane, it les free. in the cytoplasm 
and finally disappears. Like the nuclear membrane and nuclear 
sap it cannot, therefore, be considered as a permanent part of 
the nucleus. 
Metaphase. As the fibers form the spindle the chromosomes 
quickly become arranged in a single plane at the equator of the 
spindle. The stage during which they are in this position is 
called metaphase (Fig. 229, G). By the end of metaphase each 
chromosome has separated lengthwise into two daughter chro- 
mosomes. The splitting, however, may take place before meta- 
phase and even as soon as early prophase. 
Anaphase. After metaphase one of each pair of daughter 
chromosomes travels to one pole, and the other chromosome of 
each pair to the opposite pole (Fig. 229, H). The stage during 
which the daughter chromosomes move from the equatorial 
region of the spindle toward the poles is known as anaphase. 
Telophase. When the chromosomes reach the poles, they 
collect into a more or less solid-appearing mass. This marks 
the beginning of telophase (Fig. 229, J, 7). Soon clear droplets of 
karyolymph appear within the mass of chromosomes and also be- 
tween the outermost chromosomes and the cytoplasm(Fig. 229, K), 
