_Distribution._--Mysore and the Carnatic, and Ceylon.

41. Pappophorum, _Nees._

This is a perennial gra.s.s. Spikelets are contracted spiciform panicles, 1- to 3-flowered, rachilla is jointed at the base. There are 5 to 7 glumes in the spikelet. The _first_ and the _second glumes_ are membranous, keeled 3- to many-nerved, persistent. The _third_ and the fourth glumes are much shorter (excluding the awns) than the first two, coriaceous, orbicular, concave, obscurely many-nerved, cleft into nine or more equal or alternately longer long-ciliate erect awns. The fourth and the subsequent glumes are imperfect and they get gradually smaller and smaller, the last glume being represented only by a rudimentary glume with three awns. Lodicules are dolabriform and two. Stamens are three. Styles are free. Grain is obovoid or oblong, free.

[Ill.u.s.tration: Fig. 215.--Pappophorum elegans.]

=Pappophorum elegans, _Nees._=



This gra.s.s is perennial with wiry roots. Stems are erect ascending from a swollen woody base, thinly hairy and rarely glabrous, pale green and sometimes with red blotches, wiry, varying in length from 1 to 3 feet.

The _leaf-sheath_ is thinly p.u.b.escent, some hairs being minutely gland-tipped.

The _leaf-blade_ is narrow, linear-lanceolate, sharply ac.u.minate, covered both above and below with hairs, many of which being minutely gland-tipped, convolute when young. The _ligule_ is a ridge of hairs.

Nodes are p.u.b.escent.

The _inflorescence_ is a panicle with short branches, 1 to 3 inches long, rachis is p.u.b.escent; peduncle is 2 to 4 inches long, p.u.b.escent.

The _spikelets_ are pale green, sometimes purple tinged and appearing white when mature, softly p.u.b.escent, about 1/4 inch long including the awn; the rachilla is produced and disarticulates above the two lower glumes.

[Ill.u.s.tration: Fig. 216.--Pappophorum elegans.

1 and 2. The first and second glumes; 3. the third glume and its palea; 4. palea of the third glume; 5. lodicules, stamens and ovary; 6 and 7.

fourth glume and its palea; 8 and 9. fifth glume and its palea; 10 and 11. sixth and seventh glumes.]

There are 6 or 7 glumes in the spikelet. The _first glume_ is lanceolate, acute, softly hairy, usually 9-nerved, or varying from 7 to 12 (some nerves do not reach the apex), about 1/4 inch long. The _second glume_ is similar to the first but a little longer and both the glumes have broad hyaline margins. The _third glume_ is broadly orbicular, concave, sub-chartaceous, 9-nerved, densely villous and with a tuft of hairs at the base where it joins the rachilla, cleft into 9 awn-like lobes, bis.e.xual and paleate; the awns are alternately long and short, subulate, plumose in the lower half and scabrid above, the palea is oblong-ovate, sub-chartaceous, with two p.u.b.escent keels, bifid at the apex, and with 3 purple anthers. The _ovary_ is ovoid or ovoid-oblong, with two white stigmas. _Lodicules_ are two, small cuneate or quadrate.

Grain ovoid or ovoid-oblong. The _fourth_ _glume_ is similar to the third glume but smaller, paleate with rudimentary anthers and two fleshy lodicules. The _fifth_, _sixth_ and _seventh glumes_ are imperfect and gradually decreasing in size, and with awns varying in number from 5 to 8, 3 to 5, and 1 to 3, respectively, minutely paleate or not.

This gra.s.s grows well in black cotton and rich loamy soils and is a hardy one. Cattle seem to eat this gra.s.s.

_Distribution._--Fairly common in the plains in the Deccan districts and in the Coromandel coast districts.

42. Eragrostis, _Beauv._

These are slender, glabrous, annual or perennial gra.s.ses. Stems are usually erect or geniculately ascending, very rarely prostrate. Leaves are narrow. Inflorescences are open or contracted panicles, rarely spikes. Spikelets are usually strongly laterally compressed, 2, to many-flowered and not articulate at the base; rachilla is tough and persistent, jointed above the empty glumes and in some also between the flowering glumes, not produced beyond the last glume. Glumes are many, broad, obtuse, acute or mucronate, never awned, dorsally rounded and keeled; the first and the second glumes are much shorter than the spikelet, equal or unequal, empty, persistent or separately deciduous, 1-nerved or the second 3-nerved, usually membranous. Flowering glumes are imbricating, at length deciduous from the rachilla, 3-nerved, all bis.e.xual or the uppermost and rarely the lowest imperfect, ovate to lanceolate, membranous to chartaceous, usually glabrous, the lateral nerves short not reaching the mid nerve; palea are broad, membranous, deciduous with its glume or persistent on the rachilla with two ciliate smooth or scabrid keels. Stamens are three rarely two. Ovary is glabrous with two styles ending in plumose stigmas. Grain is minute, globose, obgloboid or obovoid, free in the glume and the palea.

KEY TO THE SPECIES.

A. Spikelets panicled.

B. Rachilla of spikelets more or less jointed and breaking up from above downwards.

Panicle more or less contracted and margin of flowering glumes not ciliate.

Spikelets 1/20 to 1/6 inch long; grain obovoid; stamens 2; panicle narrow interrupted, 6 to 18 inches long 1. E. interrupta.

BB. Rachilla of spikelets tough, persistent; flowering glumes falling away from base upwards.

C. Spikelets pedicellate.

Spikelets flat, ovate-elliptic or oblong, lateral nerves of flowering glumes very prominent and straight, almost percurrent; palea deciduous with their glumes 2. E. amabilis.

Spikelets less compressed, linear or linear-oblong; lateral nerves less prominent; not fascicled, long pedicellate and divaricate when ripe.

Leaf margins without glands. Spikelets versatile, narrow, linear 1 inch or more long, branches of panicle solitary 3. E. tremula.

Leaf margins glandular.

First glume 1-nerved and second glume 3-nerved 4. E. major.

First glume and second glume 1-nerved 5. E. Willdenoviana.

Spikelets small, 1/4 inch or less, branches of panicle whorled 6. E. pilosa.

CC. Spikelets sessile and jointed on the very short densely crowded branchlets of a tall, narrow raceme like panicle, deciduous, acute, much compressed, imbricate and secund 7. E. cynosuroides.

AA. Spikelets in a long terminal spike.

Spikelets distichously spreading, secund, keels of palea winged 8. E. bifaria.

=Eragrostis interrupta, _Beauv._=

(_Var. Koenigii_, Stapf.)

This is a tall gra.s.s, annual or perennial, with erect stems 1 to 3 feet or more.

The _leaf-sheath_ is glabrous and close. The _ligule_ is a short, fimbriate membrane. _Nodes_ are glabrous.

The _leaf-blade_ is narrow, flat, ac.u.minate, glabrous on both sides, 3 to 10 inches long.

The _panicle_ is erect, narrow, contracted, with branches in pseudo-whorls and varying in length from 6 to 18 inches, branches are slender, filiform, two or more arising from the same level, 1 to 3 inches long.

The _spikelets_ are small, pedicellate, smooth, usually 6 to 14-flowered, pale but often tinged with red, the rachilla is jointed between the flowering glumes, and breaks away from above downwards. The empty _glumes_ are very small, subequal, ovate-oblong, hyaline, obtuse and 1-nerved. Floral _glumes_ also are small but slightly longer than the empty ones, ovate-oblong, obtuse and paleate, palea is linear-oblong with smooth or scabrid keels. _Stamens_ are two with small anthers.

Grain is obovoid.

[Ill.u.s.tration: Fig. 217.--Eragrostis interrupta. Var. Koenigii.

1. Two spikelets; 2 and 3. empty glumes; 4. empty glumes with two flowering glumes and their palea; 5. flowering glumes and palea; 6.

ovary and two stamens; 7. grain.]

This gra.s.s is a very variable plant and has a few varieties. The one described above is Var. _Koenigii_ Stapf., and this is the one that occurs very widely. The other two varieties which occur very rarely are (1) _diarrhena_ Stapf. and (2) _tenuissima_ Stapf. The former is a tall plant with very narrow panicle and spikelets and the latter either tall or short and with a panicle bearing very slender divaricate branches.

This gra.s.s usually occurs in clayey soils especially on the bunds and in the paddy fields.

_Distribution._--Throughout India, Burma and Ceylon. Also in tropical Asia and Africa.

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