none Amount of the stained neurosecretory material (NSM) was studied in the neurosecretory cells (NSC) of the brain and neurohaemal organs of the larvae of Alysia manducator Panz. at different physiological states. In active development at 20 degree NSM is found only in the NSC of the first medial group of the brain. In any type of the diapause, both "cold" and "warm", stained NSM is present in all parts of the neurosecretory system of the larvae. At long "cold" diapause there are definite cycles of accumulation of the stained NSM in the NSC of the first medial and lateral groups. Maximum amount of the NSM in the medial NSC is observed about a month before than in the lateral NSC. During reactivation after the "cold" diapause a rapid disappearance of the accumulated NSM from all parts of the neurosecretory system is observed.