FERTILIZATION REACTION IN ECHINODERM EGGS. 275 



(k) Cytolysis consists of an irreversible coagulation of the egg 

 cytoplasm and appears to be due to the fact that the egg after 

 the action of cytolytic agents is left without a resistant surface. 

 It consequently ruptures and this injury leads to coagulation. 

 Probably cytolysis bears no relation to activation. 



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