56 WHAT IS LIFE 



to be that of a piece of tape along both edges of 

 which small beads have been sewn. Then the piece 

 of tape is split longitudinally, so that we now have 

 two narrow bands of linin each with its single row 

 of chromatin granules. When these processes have 

 taken place in many though not in all cases the 

 nuclear wall disappears and two little bodies, called 

 centrosomes, come to lie one at either side of the 

 cell. The chromosomes, for so the linin bands with 

 chromatin beads are called, arrange themselves 

 between the centrosomes in such a manner as to 

 form a spindle-shaped figure with its broadest part 

 in the centre of the cell and its apices at either side 

 and converging on the centrosomes. Meantime the 

 cytoplasm, or cell-protoplasm has also been re- 

 arranging itself in the neighbourhood of the cen- 

 trosomes, forming around them a series of rays, so 

 that there are at each side of the cell two figures 

 resembling conventional representations of the sun, 

 between which is the spindle-shaped basket of 

 chromosomes. 



The chromatin is now no longer arranged along 

 the edges of the linin bands as it was at first, but 

 becomes gathered together about the equator of the 

 spindle, that is at its widest portion which is 

 situated at the centre of the cell. 



All these events may be considered as having 

 been preparatory to the great business of division 



