THE metabolism of ribonucleic acid (RNA) in regenerating wound tissue may be expected to be of special importance since the synthesis of protein is one of the principal metabolic activities of this tissue1,2. The relative amount of RNA in this tissue at different stages of regeneration should give some insight into the protein metabolism. A complicating factor is the fact that considerable amounts of two quite different types of protein are formed, the intracellular ‘metabolically-active’ proteins, and collagen.