Cardiac Vagal Afferent Fibres in the Cat and the Frog

Summary. Further evidence has been obtained that the large afferent fibres of the cardiac vagus derive from endings of auricular origin. These nerve endings act as stretch receptors and display a common mode of action. It has been proven that the cardiac depressor reflex is elicited only by the stimulation of small fibres of the δ‐type of cardiac origin. It has been shown that the auricles of the frog's heart possess stretch receptors of the same type as those found in the cat.