| 1 | Flowering stems solitary, arising from the centre of a tuft of normal basal leaves; usually also 1-several cauline leaves with well developed leaves present. Lower bracts of the inflorescence foliaceous, the lowest overtopping the inflorescence. |
| 1' | Flowering stems several, scapiform, arising from the axils of the lower leaves or below the leaves; cauline leaves when present reduced to sheaths. Bracts of the inflorescence small, not foliaceous, none of them overtopping the inflorescence. |
| 2 | Inflorescence paniculate, with well developed rays. |
| 2' | Inflorescence densely contracted, capituliform or capitate. |
| 3 | Glumes obtuse, not mucronulate, 1½-2¼ mm long. Anthers oblong, ½-¾ mm long. Nut 1½-3 mm long |
| 3' | Glumes acute, mucronulate by the slightly excurrent mid-nerve, 4-5 mm long. Anthers linear, c. 1½ mm long. Nut 3-4 mm long |
| 4 | Stems rather robust, 2-3 mm ø. Glumes chartaceous, acutish, with narrow scarious margins, 4-5 mm long. Anthers c. 1½ mm long. Nut with a narrow acute beak |
| 4' | Stems very slender, 1-1½ mm ø. Glumes thinly membranous, obtusish, 3-3½ mm long. Anthers ½-¾ mm long. Nut with a broad obtusish beak |
