CELL MULTIPLICATION 125 
the distribution of the chromosomes. At this stage it becomes 
apparent that each chromosome consists of two pieces or halves 
each apparently having split longitudinally. The halves of each 
chromosome now separate, pass to opposite ends of the cell where 
the new nuclei are formed. Thus each new nucleus gets as many 
halves, which soon grow to full size chromosomes, as there were 
chromosomes in the parent cell. As the new nuclei are forming 
Fic. 110. — Cell division. a, cell in resting stage. b, chromatin formed 
into a thread. c, the thread of chromatin broken into segments called chromo- 
somes. d, chromosomes arranged across the cell for division. Notice the 
threads called spindle fibers running through the cell and that the nuclear 
membrane has disappeared. e, chromosomes have split and the halves are 
passing to opposite ends of the cell. f, chromosomes have reached the points 
where they are to form new nuclei. g and h, new nuclei and cross wall be- 
tween them forming. After Stevens. 
a cross wall is formed, which divides the cytoplasm, and cell divi- 
sion is now complete. Instead of one cell there are now two, 
each of which after growing to full size will divide in the same 
manner as the parent cell. 
Except in certain regions where cell multiplication is the spe- 
cial function, most cells of the plant sooner or later lose their 
ability to grow and divide as a result of their modifications 
which adapt them to their special functions. Thus after cells are 
