Uric acid injected into the normal dog is recovered in the urine largely as allantoin. Following complete removal of the liver there is a marked increase in the uric acid content of the urine so that the amount of uric acid excreted is of the same magnitude as the allantoin excretion of the normal dog. The excretion of allantoin is thus diminished in the absence of the liver, and uric acid injections fail to increase allantoin excretion; almost all of the uric acid injected may be recovered as uric acid in the urine. The destruction of uric acid and the formation of allantoin is entirely prevented by the removal of the liver.