KEY TO THE SUBGENERA

1Petals connate at least halfway up. Leaves usually not becoming yellow when drying, not discolouring, spirally arranged, entire. Flowers very fragrant. Seeds and embryo straight. Spp. 1-2
1'Petals connate only at the very base. Leaves usually becoming more or less yellow or greenish yellow when dried. Leaves spirally arranged or distichous, exceptionally in pseudowhorls. Flowers not or mostly only faintly fragrant. Seeds and embryo straight or curved. Spp. 3-58.