Abstract
Histamine had practically no effect even when administered in very large amounts whereas adrenalin had a marked and long continued pressor action. Like adrenalin the effect of acetyl-choline and pituitrin was similar to that observed in warm-blooded animals but of a comparatively longer duration. Choline in small amounts caused only a slight response whereas in large doses it gave a marked rise in blood pressure. No skin reactions to various forms of injury could be observed in the skate, but both pressor and depressor reflexes were noted following stimulation of the skin and abdominal viscera.