3 feet and the erect ones from 10 to 18 inches or more.

The _leaf-sheaths_ are terete or somewhat compressed, glabrous,
sometimes ciliated near the node and shorter than the internode. The
_ligule_ is a truncate membrane, slightly ciliate or not. _Nodes_ are
bearded.

The _leaf-blades_ in the prostrate branches are crowded, short
linear-lanceolate, finely acuminate, soft, shortly hairy along the
nerves, sparsely ciliate near the rounded base, varying in length from 1
to 2 inches and in breadth 1/8 to 1/4 inch; but on the flowering
branches the leaves are longer, sometimes as long as twelve inches with
bigger sheaths.

[Illustration: Fig. 153.--Andropogon pertusus.

1. A portion of a spike; 2. a pair of spikelets; a. sessile and b.
pedicelled; a-1. first glume; a-2. second glume; a-3. third glume; a-4.
fourth glume and awn; a-5. ovary and stamens; a-6. grain; b-1. first
glume of pedicelled spikelet front and back; b-2. second glume front and
back; b-3. third glume.]

The _inflorescence_ consists of three to nine, slender, flexuous, erect,
purplish spikes, 1 to 2 inches long, alternately arranged on a thin,
long, slender, smooth peduncle of about six inches; _rachis_ is slender
and the joints and pedicels are densely silky with long hairs.

The _spikelets_ are in pairs, one sessile and one-pedicelled, both are
equal, purplish or pale. The _sessile spikelet_ consists of four glumes
and contains a complete flower and the callus is short and bearded with
long hairs. The _first glume_ is coriaceous, oblong-lanceolate, acute,
truncate or emarginate, slightly hairy, or glabrous with a deep pit
above the middle (sometimes with two or three pits also) 7- to 9-nerved
with a few long hairs below the middle and with margins infolded and
shortly ciliate. The _second glume_ is lanceolate-acuminate and finely
pointed at the tip and the point projecting slightly beyond the first
glume, 3-nerved or 3- to 5-nerved, membranous, slightly hairy or
glabrous, obscurely keeled. The _third glume_ is thin, membranous,
shorter than the second glume, linear-oblong, subobtuse or acute at the
tip and nerveless. The _fourth glume_ is the base of the awn and the
_awn_ is not twisted, bent at about the middle, 1/2 to 2/3 inch long;
there is no palea. _Anthers_ are three and yellow; _stigmas_ purple. The
grain is oblong-obovate, slightly transparent.

The _pedicelled spikelets_ are slightly narrower than the sessile,
generally not pitted (thoug