A Handbook Of Some South Indian Grasses - Part 36
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Part 36

The _leaf-sheath_ is thin, somewhat loose, usually glabrous, rarely spa.r.s.ely hairy. The _ligule_ is a short membrane irregularly cut at the top. The _nodes_ are glabrous.

The _leaf-blade_ is linear, very finely ac.u.minate, rough on both the surfaces, thinly and very spa.r.s.ely hairy; the base of the blade is contracted and purple tinged towards the margin, midrib is prominent with three or four main veins on each side; the margins are very finely, closely serrate.

[Ill.u.s.tration: Fig. 211.--Dinebra arabica.

1 and 2. The front and back view of a portion of a spike; 3. spikelet; 4, 5 and 6. the first, second and third glumes; 7. palea of the third glume; 8. lodicules, ovary and stamens.]

The _inflorescence_ is a long erect narrow pyramidal panicle varying in length from 2 to 16 inches; the lower branches sometimes bear several spikes and attain 6 inches in length; the _peduncles_ are short or long, purple tinged and the main _rachis_ is smooth except at the top, angular and grooved. The _spikes_ are numerous, greenish or purple tinged, slender, erect or spreading or sometimes deflexed, opposite, alternate or in fascicles of two to four varying in length from 1/4 to 2-1/2 inches; the _rachis_ of the spike is trigonous, flattened out ventrally and with a ridge on the ventral side and the margins are scabrid.

The _spikelets_ are few to many in a spike, alternate, closely imbricating, sessile, about 1/6 inch long including the awns, usually three flowered, rarely less or four flowered; the _rachilla_ is very slender, jointed at the base, produced and jointed between the flowering glumes.

There are usually five _glumes_ in a spikelet and in some four or six.

The _first_ and the _second glumes_ are lanceolate narrowed into short stiff awns, equal or the second a little longer, hyaline glabrous, strongly keeled about 1/6 inch long or a little less. The _succeeding glumes_ third, fourth and fifth are very much shorter than the first two glumes, about 1/10 inch or less, ovate-oblong, subacute, white, membranous with a strong greenish nerve along the keel and two short ones close to the margin, paleate; _palea_ is shorter than the glume, membranous, oblong-obtuse, minutely 2-toothed, 2-nerved and 2-keeled.

_Stamens_ are three with small anthers. _Stigmas_ are white when young and purple when mature. _Lodicules_ are very minute. The grain is pale, brownish yellow, ellipsoidal-oblong, subacute, trigonous, rough and never smooth, with a shallow groove on the dorsal side; the embryo is about one-third the length of the grain.

This gra.s.s grows abundantly in cultivated dry fields all over the Presidency. The spikes when mature become very rough and give an acid taste. Cattle greedily eat this gra.s.s when young, but when old and in full flower some cattle do not like it so much.

_Distribution._--Throughout the Presidency in the plains. Also occurs in Afghanistan and westward to Senegal.

39. Leptochloa, _Beauv._

These are tall slender annual gra.s.ses. Spikelets are very small, compressed, 1- to 6-flowered, sessile or shortly pedicelled, alternate and unilateral on the branches of a panicle; the rachilla is produced between the flowering glumes, jointed at the base. There are 3 to 8 glumes. The first two glumes are unequal, oblong or lanceolate, 1-nerved. The third and the succeeding ones are broadly ovate, 3-nerved, paleate. Lodicules are two. Stamens are three. Grain is sub-globose, oblong or trigonous, closely invested by the glume and its palea.

=Leptochloa chinensis, _Nees._=

This is a tall annual gra.s.s. Stems are erect or geniculately ascending from a creeping root-stock, varying in length from 2 to 4 feet.

The _leaf-sheath_ is smooth, loose, the lower often broad and open. The _ligule_ is a short hyaline lacerated membrane.

The _leaf-blade_ is narrowly linear, finely ac.u.minate, somewhat coriaceous, glabrous, 6 to 18 inches long and 1/6 to 1/4 inch broad.

The _inflorescence_ is a contracted panicle, 6 to 18 inches long with spreading or suberect, alternate or opposite spikes which are capillary and vary from 2 to 4 inches in length.

[Ill.u.s.tration: Fig. 212.--Leptochloa chinensis.

1. A portion of the spike; 2 and 3. the first and the second glume; 4 and 5 the flowering glume and its palea; 6. the stamens and the ovary.]

The _spikelets_ are small, shortly stalked, 4- to 8-flowered, 1/10 to 1/6 inch with the _rachilla_ produced between the flowering glumes. The _first glume_ is small, oblong, obtuse or apiculate. The _second glume_ is similar to the first but twice as long as the first glume. The _third glume_ and the succeeding flowering glumes are ovate-oblong, obtuse or apiculate, with sub-marginal lateral veins; _palea_ are broadly oblong with silkily ciliate keels. _Anthers_ are usually very small. Grain is oblong, obtusely trigonous, or concavo-convex, red-brown and rugulose on the ventral side.

This gra.s.s is very common amidst paddy in wet lands and in wet situations.

_Distribution._--Throughout India and Ceylon in wet places. Also in China, j.a.pan and Australia.

CHAPTER X.

TRIBES VII AND VIII--FESTUCACEae AND HORDEae.

=Festucaceae= is of minor importance as it is not well represented in the South India. Only about half a dozen genera occur and most of them on the hills. The spikelets are usually 2- or more-flowered, pedicelled and in panicles, open or contracted. The rachilla is produced beyond the flowering glumes and articulate at the base just above the empty glumes.

Inflorescence a raceme, spikelets 2- to 3-flowered, turbinate; glumes single-awned. 40. Pommereulla.

Inflorescence paniculate, spikelets few or many-flowered, glumes many-nerved and many-awned. 41. Pappophorum.

Inflorescence various, spikelets 2- to many-flowered, flowering glumes 1- to 3-nerved entire, empty glumes shorter than the lowest flowering glume, grain very minute. 42. Eragrostis.

=Hordeae= is also a minor tribe and is represented by only one genus in South India.

The spikelets are one-or more-flowered, sessile, 1- or 2-seriate on the rachis, and somewhat sunk in cavities; the rachilla is jointed at the base and is produced beyond the flowering glumes, glumes awned or not.

Spikelets 1- to 3-flowered, first glume very minute or wanting, second as long as the hyaline, third spike compressed, solitary. 43. Oropetium.

40. Pommereulla, _Linn. f._

This is a short, stout, creeping perennial gra.s.s. Spikelets are 2- to 3-flowered, distichously racemed, narrowly turbinate, villous. Glumes are 5 to 7 in a spikelet. The first two glumes are narrow, membranous, persistent, the first glume being 1-nerved and shorter than the second which is 3- to 5-nerved. The third and the fourth glumes embracing the fifth and the sixth are empty, flabelliform, 4-lobed, and dorsally shortly awned. The fifth, sixth and the seventh are cuneate, obovate and 3-lobed, palea ovate, acute, and p.u.b.escent. Lodicules are two and membranous. Stamens are two to three with small anthers. Grain is oblong, compressed and free.

[Ill.u.s.tration: Fig. 213.--Pommereulla Cornucopiae.]

=Pommereulla Cornucopiae, _Linn. f._=

This is a short, stout perennial gra.s.s with stems rooting at the nodes; branches are flat, short, densely leafy, 2 to 6 inches long.

The _leaf-sheaths_ are smooth, equitant with thinly membranous margins.

The _ligule_ is a ciliated ridge.

The _leaf-blade_ is flat, linear, distichous, coriaceous, rounded at the tip, margins spa.r.s.ely ciliate, 1 to 2-1/2 inches long.

The _inflorescence_ is a terminal raceme, 1/2 to 2 inches long, half hidden by the uppermost leaf-sheath, the peduncle is flattened and 1 to 2-1/2 inches long; rachis is also flattened with a tuft of long silky hairs at the base.

[Ill.u.s.tration: Fig. 214.-Pommereulla Cornucopiae.

1. A leaf; 2. inflorescence; 3. spikelet; 4 and 5. the second and the first glume; 6 and 7. the third and the fourth glume; 8 and 9. the fifth flowering glume and its palea; 10 and 11. grain.]

The _spikelets_ are shortly pedicelled or sessile, dorsally compressed, cuneiform, about 1/3 inch, glistening, villous, not articulate at the base, 2- to 3-flowered, rachilla is narrowed downwards, resembling a callus and villous, jointed at the acute base above the empty glumes, and crowned with broad obconic empty awned glumes. The spikelets have usually seven, rarely eight glumes. The _first_ and the _second glumes_ are narrow, membranous, glistening, empty and persistent and the others are coriaceous with membranous margins. The _first glume_ is linear or linear-lanceolate, ac.u.minate, 1-nerved, scaberulous along the nerve. The _second glume_ is longer than the first, oblong-lanceolate, ac.u.minate, narrowed towards the base, inserted much above the first glume and embracing the rachilla, 3-nerved, scaberulous along the mid-nerve at the base only. The _third_ and _fourth glumes_ are half-amplexicaul, empty, epaleate, flabelliform, 4-lobed, 7-nerved, shortly awned at the back, villous; the side lobes are ac.u.minate or aristate and the central lobes are shortly awned. The _fifth_, _sixth_ and _seventh glumes_ are obovate-cuneate, 7- to 9-nerved, paleate, flower-bearing and 3-lobed, the side lobes are ac.u.minate and the central lobe is bifid and dorsally awned; palea is ovate-acute, 2-nerved and ciliolate. The _eighth glume_, if present, is neuter and imperfect, 3-lobed and shortly awned.

_Lodicules_ are minute. _Stamens_ are two or three with small anthers.

Grain is oblong, compressed, reddish brown.

This gra.s.s generally grows in gravelly and somewhat alkaline soils. So far this has been noticed and collected in Chingleput and Nellore districts.