1. A new alkaloid grantianine has been isolated from Crotalaria grantiana. 2. It is saponified by methanolic potassium hydroxide to retronecine and an acid not yet isolated in a pure state. 3. Reduction gives tetrahydrograntianine which is postulated as an amino acid. 4. Preliminary results thus indicate that grantianine may be retronecine esterified on both hydroxyls with one molecule of a dibasic acid. © 1942, American Chemical Society. All rights reserved.