Abstract:
1. The present paper was aimed at studying the role of the neuroendocrine system, particularly the sinus gland, in the spectral sensitivity of the crayfish. 2. Using the ERG, spectral sensitivity of naive adult cryfishes was compared with that of sinus gland-deprived adult animals. 3. As opposed to naive animals, the sinus gland-deprived animals show a relatively high sensitivity to UV and a low sensitivity to red. 4. Comparison of these results with those previously obtained in animals during their development evidences a similar spectral sensitivity between the sinus gland-deprived animals and the very young ones. 5. The possible role of the neuroendocrine system in the synthesis of 3-dehydroretinal-porphyropsin system is discussed.