THE CHARACTERISTICS OF ORGANISMS 



21 



The division of a cell is one of the wonders of the world. Bateson 

 wrote (1913, p. 39): "I know nothing which to a man well trained 





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Fig. 6. 



The Indirect or Karyokinetic Mode of Cell-division, i, the resting nucleus 

 with ill-defined chromosomes; 2, the chromosomes well defined; 3 and 4, 

 the chromosomes arranged in an equatorial plane; 5 and 6, the halves of 

 the longitudinally split chromosomes move to opposite poles. 



in scientific knowledge and method brings so vivid a realisation of 

 our ignorance of the nature of life as the mystery of cell-division. 



