Abstract
The effect of the light of different intensity of illumination and wavelengths on hatching was investigated by means of the hatching type.
1. The switchover of illumination from 300 lux to 5 lux or from 30 lux to 1 tux at the stage just before hatching was acted as the same stimulus from light to dark.
2. Hatching type under the continuous illumination of 1 lux was indicated as a continuous dark type, but by switchover from 1 lux to dark, it was changed to be indicated as a light to dark type II. By switchover from dark to 0.1 lux, hatching type was indicated as a dark to light type. These results show that the switchover of light in different intensity of illumination just before hatching affected hatching mode.
3. When light was switched over from the white light just before hatching, the light in wavelengths from 377 nm to 500 nm acted as the same stimulus for hatching as the white light, whereas the light in wavelengths from 590 nm to 700 nm acted as the same stimulus as darkness. The light of 540 nm acted as an intermediate stimulus between light and dark for hatching.
4. When the light in wavelengths was switched over from darkness, all of the lights in wavelengths from 377 nm to 700 nm acted as light according to the intensity of illumination.
5. The dark stimulus depended on the light in wavelengths from 590 nm to 700 nm acted not always as the same stimulus as darkness.
