Chemical analysis showed that the seeds of Argyreia nervosa contain the highest percentage of indole alkaloid constituents (0.5‐0.9%) of the genera of the Convolvulaceae thus far studied. A total of 19 indole alkaloids were identified by thin‐layer and paper chromatographic procedures. Of these, lysergene, festu‐clavine, setoclavine, isosetoclavine, agroclavine, elymoclavine, ergine, and isoergine were isolated by column chromatographic procedures and characterized by TLC and IR analyses. Penni‐clavine, chanoclavine‐I, chanoclavine‐II, ergometrine, ergometrinine, lysergic acid α‐hydroxyethylamide, isolysergol, racemic chanoclavine‐II, molliclavine, lysergol, and isolysergic acid α‐hydroxyethylamide were identified by TLC only. Of these, lysergene, setoclavine, isosetoclavine, chanoclavine‐II, racemic chano‐clavine‐II, isolysergol, and molliclavine were identified for the first time in species of the Convolvulaceae. Ergine (0.136%) and isoergine (0.188%) were found in the highest concentration. In addition, 11 unidentified indole alkaloids were detected, these being found in very low concentration. Although the pericarp showed the same alkaloid pattern as the seeds, the concentration was much lower (0.0015%). No alkaloids could be delected in the vegetative tissues of nonflowering specimens. Copyright © 1973 Wiley‐Liss, Inc., A Wiley Company