KARYOKINESIS 251 



Between the two points the spindle takes shape, and 

 we can recognise in it radiating lines of attraction leading 

 towards the opposing points. That is, the spindle is not 

 a structure ; in fact, it is not properly a " spindle " at all. 

 Its lines are surely not anything else than the arrangement 

 of protoplasmic granules along the force-lines leading to 

 the poles — a purely temporary phenomenon. Further, the 

 steady divergence of the spindle lines towards the equator 



N\f> Sne'r/'o ■ 



bd 





£ ^'AX0'^. 



Fig. 86. — A, lines of magnetic force of a bar magnet. N, north 

 pole ; s, south pole, b, the lines issuing from the surface of the 

 north end of a cylindrical bar magnet. 



of the cell would prove, as is shown above, that they are 

 not continuous from one pole to the other, but are indica- 

 tions of mutual polar repulsion. 



Lying suspended between the achromatic poles is the 

 nuclear chromatin, stationary because attracted towards 

 both by reason of its containing blended closely together 

 " elements " peculiarly attractable to the opposing poles. 

 Thus the lines of mutual polar repulsion are also the lines 



