37. Eleusine, _Gaertn._
These are annual or perennial gra.s.ses. Leaves are long or short. The spikelets are sessile, 3 to 12 flowered, 2 to 3-seriate, secund, laterally compressed and forming digitate whorled or capitate spikes, not joined at the base; rachilla continuous between the flowering glumes. The glumes in a spikelet are few to many, keeled. The first two glumes are subequal or unequal, persistent; the first glume is 1-nerved and the second glume is 1- to 7-nerved. The flowering glumes are 3-nerved, paleate; palea is complicate; keels are strong, scabrid or ciliate. Lodicules are two, cuneate. Anthers are short. Styles distinct and short. Grain is free, rugose, and the pericarp is hyaline and loose.
KEY TO THE SPECIES.
Spikelets pointing upward at an acute angle with the rachis of the spike.
Spikes 1 to 5 inches long, digitate, erect. 1. E. indica.
Spikes 1/6 to 1/4 inch or a little more, capitate, spreading. 2. E. brevifolia.
Spikelets spreading at right angles with the rachis of the spike, spreading or erect. 3. E. aegyptiaca.
=Eleusine indica, _Gaertn._=
This is a tufted annual gra.s.s with short, erect, somewhat compressed, glabrous stems, 1 to 2 feet high.
The _leaf-sheaths_ are compressed, distichous, ciliate. The _ligule_ is a ridge of hairs.
The _leaf-blades_ are narrow-linear, as long as the stem, glabrous or with a few scattered hairs near the mouth, ac.u.minate, base not contracted, 12 to 20 inches long and 1/8 to 1/6 inch broad.
The _spikes_ are elongate, digitate, 2 to 7, 2 to 5 inches long, all in a terminal whorl and sometimes with one or two lower down, and with the axils glandular and hairy; the _rachis_ is slender and dorsally flattened.
[Ill.u.s.tration: Fig. 206.--Eleusine indica.
1. A portion of the spike; 2. a spikelet; 3. flowering glumes and their palea with the rachis; 4 and 5. the first two glumes; 6 and 7. flowering glume and its palea; 8. the ovary, stamens and the lodicules; 9 and 10.
grain.]
The _spikelets_ are variable in size, 1/12 to 1/6 inch, 3 to 5, rarely 6-flowered, quite glabrous, biseriate, pointing upward at an acute angle with the rachis. All the glumes are more or less membranous. The _first glume_ is small, oblong-ovate or oblong, 1-nerved with a scabrid keel.
The _second glume_ is twice the size of the first, ovate-oblong, 3-nerved, rarely 3- to 7-nerved, glabrous, shortly mucronate at the acute apex. The _third glume_ and the succeeding flowering glumes are larger than the second, ovate-oblong, subacute, 3-nerved and paleate; _palea_ is shorter than the glume, glabrous. _Stamens_ are three.
_Lodicules_ are small and cuneate. The grain is oblong, obtusely trigonous, broadly and shallowly grooved dorsally with concentric minute tubercled ridges covered with a loose pericarp.
This gra.s.s is fairly common in somewhat wet places in the plains and low hills.
_Distribution._--Throughout India and Ceylon.
=Eleusine brevifolia, _Br._=
This is an annual gra.s.s. Stems are creeping and spreading from the root, and ascending from a dec.u.mbent base, generally slender and small, but sometimes large and proliferously branched, leafy, 3 to 7 inches long.
The _leaf-sheath_ is compressed and glabrous. The _ligule_ is a very short membrane, ciliate at the margin or obsolete.
The _leaf-blade_ is linear, acute, with a subcordate or rounded base 1/2 to 2 inches long and 1/8 to 1/6 inch broad.
The _spikes_ are usually many, sessile and crowded in globose heads, varying in diameter from 1/3 to 2/3 inch.
[Ill.u.s.tration: Fig. 207.--Eleusine brevifolia.
1. A spikelet; 2 and 3. the first and the second glumes; 4 and 5. the third glume and its palea 6. lodicules, ovary and stamens.]
_Spikelets_ are sessile, biseriate, ovate-oblong, 1/8 to 1/6 inch long, 4- to 10-flowered. The _first two glumes_ are membranous, ovate-oblong, glabrous, ac.u.minate and shortly awned, the _first glume_ is shorter than the second, 1- to 3-nerved, the _second glume_ is longer than the first, 3- to 5-nerved, and the nerves are very close to the middle one in the keel. The _third_ and the succeeding _glumes_ are ovate, cuspidately ac.u.minate, 3-nerved, nerves villous below the middle and paleate; _palea_ is oblong, lanceolate, truncate and minutely 2-toothed, keels villous below the middle. _Anthers_ are small. _Lodicules_ are also small and cuneate. _Styles_ are long and slender. Grain is...o...b..cular to ovate, concavo-convex, red-brown, and transversely rugose.
This gra.s.s is usually found in somewhat damp situations all over the Presidency, though somewhat local in its distribution.
_Distribution._--Sandy sh.o.r.es of the Coromandel and Carnatic coasts.
[Ill.u.s.tration: Fig. 208.--Eleusine aegyptiaca.]
=Eleusine aegyptiaca, _Desf._=
This gra.s.s is an annual with erect or creeping branches. Stems are erect or prostrate, compressed, smooth, spreading and rooting at the nodes, 6 to 18 inches long. Nodes are thickened and sometimes proliferous.
The _leaf-sheath_ is compressed and glabrous. The _ligule_ is short and membranous.
The _leaf-blade_ is linear, tapering to a fine point, flat, glaucous, glabrous or hairy, 1 to 6 inches long and 1/12 to 1/6 inch, wide.
[Ill.u.s.tration: Fig. 209.--Eleusine aegyptiaca.
1. Front and back views of a portion of spike; 2. a spikelet; 3 and 4.
the first and the second glumes; 5 and 6. flowering glume and its palea; 7. ovary and anthers.]
_Spikes_ are digitate, 2 to 6, 1/2 to 1-1/2 inches long. _Spikelets_ are flat, densely crowded on one side of the floral axis, spreading at right angles, 3- to 5-flowered, _glumes_ five to seven. The _first glume_ is ovate acute. The _second glume_ is equal to the first or slightly longer, broadly ovate, awned. The flowering _glumes_ are ovate, mucronate or awned, paleate; _palea_ is shorter than the glume, ovate-oblong, obtuse or 2-fid. _Anthers_ are small. Grain is reddish, rugose and sub-globose.
This is a very common gra.s.s occurring as a weed in cultivated fields and in open places. It is a well-known fodder gra.s.s.
_Distribution._--Throughout the plains in India and Ceylon.
38. Dinebra, _Jacq._
These are leafy annual gra.s.ses. The inflorescence is a narrow pyramidal raceme of slender, spreading or deflexed spikes. Spikelets are small, biseriate and crowded on one side of the spike and not jointed at the base; rachilla is slender, jointed and produced beyond the flowering glumes and bearing an imperfect glume. There are four to five glumes.
The first two glumes are the longest, lanceolate, 1-nerved, keeled and awned. The second glume is slightly longer than the first. The third and the fourth glumes are very small, hyaline, broadly ovate, 1-nerved.
Lodicules are present. Stamens are three and anthers didymous and small.
Grain is narrowly ovoid and trigonous.
[Ill.u.s.tration: Fig. 210.--Dinebra arabica.
1. Full plant; 2. leaf showing the ligule.]
=Dinebra arabica, _Jacq._=
This gra.s.s is an annual with stems erect or with a geniculate base, tufted, slender or stout; some of the lower nodes of the geniculate part of the stems bear roots; the internodes are green or purple tinged and glabrous.