Abstract
In Ringer's solution to which urea or glycerol was added the stomach muscle and sartorius of the frog lost K and Na and a corresponding amount of water. Under the same conditions sucrose produced a greater loss of water, but had no effect on cations. In isosmotic solutions of erythritol stomach muscle swelled more than in sucrose solutions, but swelling could be prevented by adding 1 mm CaCl2/l. In such solutions the fibers lost about half of their cations. Osmotically this loss was approximately balanced by the amount of erythritol which entered. In solutions of sucrose the fibers lost less K and Na and took up a correspondingly smaller amount of the nonelectrolytes.