Fig. 3. Increases in cGMP (A,D) and IP₃ (B,E) contents during the latent periods of Ca²⁺ transients (C,F) in A. crassispina (A-C) and H. pulcherrimus eggs (D-F). Data for the initial 50 seconds of Fig. 2 were normalized to the cGMP content, IP₃ content or [Ca²⁺]_i of the unfertilized eggs. Arrows indicate the onset of fertilization potential.