The alkaloid composition of the following three Hawaiian Rauwolfia species-R. sandwicensis A.DC., R. degeneri Sherff and R. mauiensis Sheriff-was determined. Aside from the known aklakoids serpentinine, ajmaline, tetraphylline and tetraphyllicine there were encountered trace amounts of two new dihydroindole alkaloids, mauiensine and sandwicensine as well as larger quantities of an isomer of ajmaline, which was named sandwicine (C20H26N2O2). Since sandwicine and ajmaline yield different dihydro derivatives which are convertible by lead tetra-acetate oxidation to a common indole hemi-acetal, sandwicine represents the C-17 epimer of ajmaline. Dihydrosandwicine was found to be identical with tetrahydroajmalidine, the sodium borohydride reduction product of ajmalidine, thereby proving that ajmalidine is 17-dehydroajmaline. © 1957.