The entire blood of the adrenal gland of a dog, acting as the donor, passes into the jugular vein of a 2nd dog, the recipient. Certain substances (nicotin, cytisin, lobelin, iodome-thylate of hordenin or some of the quaternary ammonia compounds) injected into the donor produce marked discharge of adrenalin, which produces in the recipient: great elevation of blood pressure, acceleration of the denervated heart, intestinal inhibition, contraction of the spleen and denervated limb, and hyperglycemia. The effects are produced by direct action on the denervated adrenal gland. Discharge of adrenalin lasts 1 or 2 min. and can reach or exceed 0.1 mgm. per min., with rapid return to the initial rate or less. The effect can be repeated several times; continuous injection produces prolonged but diminishing discharge. Ergotoxin lessens, ut does not entirely abolish, the action of nicotin. In the adrenalectomized dog hypertension, bradycardia and intestinal movements can still be observed. Nicotin probably excites the adrenal secretory centers and ganglia but its main excito-secretory action is directly on the adrenal medulla.