A striking depression in rate of flow of the nasal mucous blanket was observed in 4 water-deprived herring gulls, in contrast to 10 normally hydrated gulls. The observation was repeated in a series of 20 water-deprived and 10 normally hydrated chickens. In both species normal mean rate of flow was about 10 mm/minute. Two gulls and 2 chickens that were deprived then rehydrated showed a normal rate of motion of the blanket. Anchoring of the mucous sheet to the mucosal surface by fine strands of mucus was seen in whole mounts and histological sections of conchae of dehydrated baby chicks.