Sub. Tribe 4. Apludeæ.
- Spikelets three on an inarticulate rachis 24. Apluda.
Sub. Tribe 5. Rottboellieæ.
- Spikelets similar or dissimilar, 1- to 2-flowered, solitary, 2-
or rarely 3-nate on the internodes of an articulated spike or
raceme, not awned; the first glume is not keeled, sunk in a cavity
of joints of the rachis; sessile spikelets 4-glumed.
- Sessile spikelets single; first glume flat 25. Rottboellia.
- Sessile spikelets geminate in all except the uppermost joints 26. Mnesithea.
- Sessile spikelets binate; first glume globose, pitted 27. Manisuris.
Sub. Tribe 6. Eu-Andropogoneæ.
- Spikelets are dissimilar, 1-flowered, 2-(rarely) 3-nate on the
whorled articulate branches of simple or compound racemes or
panicles; glumes four, first glume not keeled, fourth glume usually
awned.
- Spikelets binate below and 3-nate at the top on a spicate or panicled inflorescence 28. Andropogon.
- Spikelets in two superposed series. Upper series of one or more
sessile bisexual or female spikelets with one terminal pedicelled
male spikelet.
- Rachis jointed above the involucral spikelets 29. Anthistiria.
- Rachis jointed below the involucral spikelets 30. Iseilema.
16. Coix, L.
These are tall monoecious annual or perennial grasses. The inflorescences are terminal or axillary spiciform racemes. The lowest-spikelet in the raceme is female and this is enclosed in a bract which at length becomes hardened, polished and nut-like and the other spikelets above it are male. The male spikelets are 2- to 3-nate at each node of the rachis, 1 sessile and 1 or 2 pedicelled, lanceolate and 4-glumed. The first and the second glumes are subequal and empty, and the first glume is winged along the inflated margins. The third and the fourth glumes are hyaline, with three stamens or empty. The female spikelet is ovoid acuminate and has four glumes. The first glume is chartaceous and the others are thin and gradually smaller. The grain is orbicular, ventrally furrowed and enclosed by the polished hard bract.