These are tall monoecious annual or perennial grasses. Inflorescences consist of spiciform racemes with spathaceous bracts; rachis is jointed. Racemes may all be male or with one or two female spikelets at the base. Male spikelets are geminate, one sessile and one pedicelled, 2-flowered or imperfect, and with four glumes, which are subequal. The first glume is membranous, many-nerved, shallowly concave and with a narrow membranous margin. The second glume is narrower, ovate, acute, 5- to 9-nerved. The third glume is membranous, oblong, acute, 3- to 5-nerved, paleate and with three stamens. The fourth glume is very slender, hyaline, linear, paleate with three stamens or empty. Female spikelets are broadly oblong, 1-flowered and with four glumes. The first glume is thick, coriaceous and closely embraces the rachis of the spike by its involute margin and the other glumes are within. The second glume is oblong, many-nerved. The third is narrowly oblong, 3- to 5-nerved, empty. The fourth glume is very narrow, truncate, 3-nerved, paleate. Styles are very long with slender stigmas. Grain is small, fusiform, terete and enclosed in the nut-like polished and hardened first glume. =Polytoca barbata, _Stapf._= This is an erect, tall, stout, freely branching, leafy, monoecious perennial grass. The stems are terete, 3 to 6 feet high. The _leaf-sheaths_ are long, glabrous, or with scattered tubercle-based bristly hairs. The _ligule_ is a narrow membrane. The _nodes_ have a ring of soft long hairs. The _leaf-blades_ are long, flat, linear, acuminate, with a stout midrib and thickened serrate margins, scabrid above and sometimes with a few tubercle-based hairs, 10 inches to 2 feet long and 1/4 to 3/4 inch broad. The _inflorescence_ consists of paniculate spike-like racemes terminating the branches and at first enclosed in spathiform bracts, the lower and outer spathiform bracts are one inch or more in length with a long awn at the tip, and the inner proper sheaths are oblong, awned and about 1/2 inch long. The raceme consists of one or more female spikelets at the base and a number of male spikelets above, appearing as if sessile on the top of the female spikelet, but really articulate with the internode below it which is enclosed by the first glume of the female spikelet. [Illustration: Fig. 127.--Polytoca barbata. 1. Inflorescence; 2, 3, 4 and 5. the first, second, third and the fourth glume, respectively, of the male spikelet; 4a and 5a. palea of the third and the fourth glume, respectively; 6. the first glume of the sessile spikelet; 7. female spikelet; 8, 9 and 10. the second, third and the fourth glume, respectively; 11. palea of the fourth glume; 12. ovary.]