Fig. 5. Timing of hatching monitored in the 24 h L:D cycles. (A) Control groups. Open circles indicate the time of hatching in intact females, and solid triangles indicate the time of hatching in the females immersed in ice water for 10 min. (B) Hatching and larval release of females from which the compound eye—retina complex was removed (experiment II-1; Fig. 2C). (C) Hatching and larval release of females from which the optic peduncles had been removed up to the medulla externa (ME) (experiment II-2; Fig. 2C). (D) Hatching and larval release of females from which the optic peduncles had been removed up to the medulla interna (MI) (experiment II-3; Fig. 2C). (E) Hatching and larval release of females from which a triangle window on the eyestalk exoskeleton had been removed and replaced (experiment III-1; Fig. 2E). The 24 h L:D cycle is shown by the horizontal bar at the top of the figure (the filled section represents the dark phase). HW connects the times of predicted high tide in the field. SS and SR indicate the times of sunset and sunrise in the field, respectively.