Abstract
A new species of ribonucleic acid (RNA) was detected in sporulating culture of Saccharomyces cerevisiae. This RNA was isolated by sucrose density gradient centrifugation and polyacrylamide gel electrophoresis and partially characterized. It has a sedimentation coefficient of approximately 20S and a nucleotide composition distinct from other known RNA species in yeast, and it hybridizes with nuclear but not with mitochondrial deoxyribonucleic acid.