THE BIOLOGY OF THE CELL SURFACE 



nated during cleavage and that this elimination is deter- 

 mined by the ectoplasm.^ 



In all the foregoing it is safe to conclude that the injury 

 to the cytoplasm is an ectoplasmic injury. We may there- 

 fore proflfer the hypothesis that in ectoplasmic behavior 

 lies the cause of the behavior of the chromosomes. Normal 

 chromosome-distribution and -combinations depend upon 

 the integrity of the ectoplasm; their aberrant behavior is 

 the eflFect of the loss of this integrity. Such behavior may 

 manifest itself in chromosomal elimination, fragmentation, 

 and the like. 



To me the conclusion seems inescapable: ectoplasmic 

 behavior determines the cytoplasmic reactions that lie at 

 the basis of nuclear activity in both normal and abnormal 

 mitoses. Where experimentally induced mutations are 

 related to visible changes in the chromosomes, as their 

 fragmentation, translocation, etc., these are not to be 

 regarded as direct effects of the experimental means 

 employed, — e.g., temperature, radiations — but as express- 

 ions of the antecedant altered cytoplasmic reactions brought 

 about by changes in the ectoplasm that evolved in response 

 to the action of the means. 



If one observes under a microscope, equipped with a 

 dark-field condensor, a suspension of Chinese ink ground 

 up in water, one sees these inanimate particles scintillating 

 back and forth in Brownian movement. One knows that 

 the shining particles are moved and are not themselves 

 motile. It is a far cry from the dance of ink-particles to 

 the orderly movements of chromosomes in a living cell. 

 And yet, it is warrantable to assume that as we look upon 

 the shifting of chromosomes in cells, their constant distribu- 

 tion during cell-division, generation after generation, we 

 behold, not a motility inherent in these bodies themselves 



^ Dubois, ig33. 



352 



