THE EXCRETION OF WATER BY THE KIDNEYS OF FROGS

Abstract

Rates of urine formation were measured by ligaturing the cloacae of frogs, and allowing the urine to escape after weighing the animals. The normal rates for frogs immersed in water varied in proportion to the body weights of the individuals; at 20[degree] they averaged 31 % of the body weight per 24 hrs. The influences of temp., concentration of NaCl in the medium, injections of water or of solutions of NaCl or urea on the rate of water excretion were studied. The total concentrations and chloride concentration of the urine were normally very low and varied with the influences tested. Diureses followed the injections but were small when the injected solutions contained NaCl.