In a previous communication1 it was shown that changes in the electrolyte pattern of the cerebrospinal fluid of dogs produced by intracisternal injections caused muscular twitching, a rise in blood pressure and disturbances of breathing. The similarity of this syndrome to that exhibited by certain patients with renal insufficiency has led to a study of experimental uremia. In the present communication no attempt will be made to summarize the extensive literature on the subject. Discussions of previous work are to be found in the publications of Fishberg,2 Becher3 and Harrison and Mason.4 Dogs were used as experimental subjects. Measurements of the blood pressure were made by a modification of the technic of Ferris and Hynes,5 the cuff employed being similar to theirs but the passage of the pulse wave being determined by palpation of the dorsal artery of the hindfoot rather than by auscultation. The