Physiological Studies on Fertilization and Activation of Fish Eggs

III. The Activation of the Unfertilized Egg with Electric Current

Abstract

1. The ripe unfertilized egg of Oryzias can be activated with direct current. The breakdown of the cortical alveoli and subsequent elevation of the chorion begin at the anodal and the cathodal sides.
2. Reaction time for the breakdown of the cortical alveoli and the propagation of the cortical change indicate that there is a gradient of excitation-conduction in the unfertilized egg. It is the highest at the animal pole and the lowest at the vegetal pole
3. Unfertilized eggs treated with narcotics (phenyl urethane and chloretone) pare rendered incapable of cortical response upon subsequent electric stimulation. The effect of narcotics is readily reversible.