§ 2. Rays present; i.e. the marginal flowers or some of them with ligulate corollas.
[*] 1. Pappus of capillary bristles, at least in the disk. (Rays all pistillate.)
Rays occupying several rows 26, 72, 73
Rays in one marginal row, and
White, purple or blue, never yellow 17, 24, 25, 26, 73
Yellow, of the same color as the disk.
Pappus (at least in the disk) double, the outer short and minute 13, 14
Pappus simple.
Scales of the involucre equal and all in one row. Leaves alternate 75
Scales of the involucre in two rows. Leaves opposite 74