e or
linear-lanceolate, acuminate, base rounded and margin with minute
serrations. It is glabrous or occasionally hairy with scattered,
tubercle-based, deciduous hairs, and varying in length from 1 to 3
inches generally (sometimes in well-grown plants it is 5 inches) and in
breadth from 1/8 to 1/4 inch. The midrib is prominent though slender at
the base and four veins are present on each side with five or six
smaller ones between them.

[Illustration: Fig. 81.--Panicum Isachne.

1 and 1a. Front and back view of a spike; 2 and 2a. back and front views
of a spikelet; 3 and 4. the first and the second glume, respectively; 5
and 5a. the third glume and its palea; 6 and 6a. the fourth glume and
its palea; 7. lodicules, anthers and ovary; 8. grain.]

The _inflorescence_ is an erect, narrow panicle consisting of spikes
varying in number from 5 to 12 and in length from 2 to 3 inches. The
_spikes_ are erect, pressed to the very slender rachis, longer than the
internodes of the main rachis, stalked or sessile, mostly simple but
sometimes the lower dividing into two or three branches, 1/2 to 1 inch
long. The rachis of the spike is very slender, angular, flexuous,
narrower than the spikelets, scaberulous with a few long cilia at the
angles.

The _spikelets_ are very small, 1/16 inch long, turned all to one side
and closely packed in two rows, oblong or oval-oblong, obtuse or
subacute, softly hairy, pale green or purplish, with very short pedicels
which are pubescent with a few long hairs towards the thickened cupular
tips.

There are four _glumes_ in the spikelet. The _first glume_ is very
small, membranous, glabrous, broader than long, cordate or triangular,
broadly but shallowly emarginate, nerveless or very obscurely 1- to
2-nerved. The _second glume_ is pale or purplish, 5-nerved, hairy, as
long as the third glume, membranous, oblong and obtuse. The _third
glume_ is pale, nearly equal to the second glume with a longitudinal
depression at the back, less hairy than the second glume, 3-nerved
(rarely 5-nerved also); _palea_ is present, and it is hyaline, shorter
than the glume, truncate or shallowly retuse, usually barren but
occasionally with three stamens. The _fourth glume_ is oblong, rounded,
coriaceous, smooth, shining, dorsally flattened, 3- or indistinctly
5-nerved; _palea_ is similar to the glume in texture and with folded
margins. There are three _stamens_ with yellow anthers. _Lodicules_ are
two, very small and di