Davey K G, Breckenridge W R
Science. 1967 Nov 17;158(3803):931-2. doi: 10.1126/science.158.3803.931.
A group of nerve cells in the rostellum become progressively more fuchsinophilic during the first 16 days of development; they then release their secretion into their axons at about the time that the first proglottid is released.