This thesis is concerned with the variations which occur in the electroencephalograms, eye-movements, and neck-muscle potentials of three species, the pigeon, rat, and chicken during prolonged recording under normal conditions, under conditions in which the animals were fatigued, and after drugs had been administered. While the recordings from the rat showed the two stages of deep sleep typical of animals, no distinctive ’’sleep” patterns were observed in the records from birds except after Nembutal had been given. The results seem to support the idea that birds do not sleep. / Thesis / Master of Arts (MA)