94 VITALISM AND SCHOLASTICISM 



attend this process of the division of a cell 

 into two parts, but in the majority of instances, 

 and invariably in the case of the cell from which 

 a new individual is to be built up, a singular 

 series of events takes place of which some 

 mention must now be made. 



In a previous chapter the structure of the 

 nucleus and cell in what is often called, though 

 the term is a misleading one, the " resting 

 stage " has been described and it will not be 

 necessary to recapitulate the facts there laid 

 down. 



Prior to the division of the cell the linin of 

 the nucleus, or most of it, becomes broken up 

 into a series of threads on which the particles 

 or granules of chromatin arrange themselves 

 along the threads like so many beads on a 



DESCRIPTION FOR FIG. III. ON PAGE 95. 



A. Resting cell with reticular nucleus and true nucleus; 

 at c the attraction-sphere containing two centrosomes. 

 B. The chromatin formed into a continuous tape, nucleolus 

 present, amphiaster (a) formed around centrosomes. C. 

 Spindle-shaped karyokinetic figure formed, consisting of 

 two centrosomes with radial arrangement of protoplasm 

 around each, equatorial plate (e.p.) of chromosomes in 

 centre. D. The equatorial plate (e.p.) has split longitudin- 

 ally (n) the cast-off nucleolus. E. The two sets of chromo- 

 somes are diverging and the interzonal fibres (i.f.) lit 

 between them, the central spindle. The centrosomes are 

 already doubled in anticipation of the next division. F. 

 The cell-body has divided and the two groups of chromo- 

 somes are in process of reconstructing themselves into 

 nuclei. G. Completion of the process of division. Two 

 cells, with fully constituted nuclei and centrosomes take 

 the place of the single cell shown in A. From WILSON. 



