This is an annual gra.s.s usually growing in tufts with fine fibrous roots and many slender spreading branches, all of them at first creeping and horizontal, rooting at the nodes and then becoming erect and varying in length from 1 to 2 feet.
Stems are very slender, glabrous or covered with scattered hairs, purplish or pale green, and branching freely towards the base.
The _leaf-sheath_ is shorter than the internodes, green or purplish, striate, externally hairy with scattered bulbous-based hairs, varying in length from 1/2 to 3 inches, the outer margin of the sheath is ciliate with long hairs and at the mouths sometimes long hairs are present, especially when the leaves are young. The _ligule_ is merely a dense fringe of long hairs. _Nodes_ are tumid, purplish, covered with long hairs.
The _leaf-blade_ is flat but convolute when young, lanceolate or linear-lanceolate, ac.u.minate, 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.
[Ill.u.s.tration: Fig. 81.--Panic.u.m 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 p.u.b.escent 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 distinct. _Ovary_ has two styles with feathery _stigmas_ white at first, but turning deep purple while withering.
This delicate and small gra.s.s occurs here and there as mere tufts especially in sheltered situations. It usually flourishes in black cotton soils amidst cholam (_Andropogon Sorghum_), although it thrives equally well in other rich soils. This is considered to be a very good fodder gra.s.s.
_Distribution._--It is fairly common all over the Madras Presidency, and goes up to 3,000 or 4,000 feet. It occurs in Africa, America and Italy.
[Ill.u.s.tration: Fig. 82.--Panic.u.m flavidum.]
=Panic.u.m flavidum, _Retz._=
This plant is a tufted annual. It branches freely from the base; branches are tufted, dec.u.mbent at first but soon becoming erect, slender, glabrous, compressed and leafy, varying in length from 1 to 3 feet.
Leaves are somewhat distichous. The _leaf-sheath_ is compressed, glabrous, sometimes with a tinge of purple, the lower ones swollen at the base and the mouth is hairy. The _ligule_ is a fringe of hairs.
Nodes are glabrous.
The _leaf-blade_ is flat, thinly coriaceous, linear-lanceolate and ac.u.minate, or ligulate with a rounded tip, 3 to 5 inches in length, 3/16 to 5/16 inch wide, glabrous or very thinly scaberulous, base rounded or slightly cordate with long white ciliate hairs on the small basal lobes.
[Ill.u.s.tration: Fig. 83.--Panic.u.m flavidum.
1 and 2. Front and back view of a portion of spike; 1a and 2a. the front and back view 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. anthers and ovary; 8. grain.]
The _inflorescence_ is a raceme of spikes, 5 to 10 inches long, erect or inclined on a short or long, glabrous, strongly channelled peduncle; the main rachis is grooved, angled and scaberulous. _Spikes_ are few or many, 1/4 to 1 inch long, erect, pressing on the rachis of the inflorescence along the groove, distant and sessile; the lower spikes are very much shorter than the internodes, but the upper equal to or longer than the internodes; the rachis of the spike is angular, flattened below, erect or slightly recurved.
The _spikelets_ are white, in two rows on a flattened rachis, obliquely ovoid or gibbously globose, glabrous, sessile, 1/8 inch in length.
There are four _glumes_. The _first glume_ is suborbicular, about half the length of the third glume, usually 3-nerved. The _second glume_ is broadly ovate, obtuse, concave, larger than the first glume and nearly equal to or shorter than the fourth glume, 7-nerved, rarely 7- to 9-nerved, nerves are anastomosing, tip rounded. The _third glume_ is broadly ovate or oblong, equal to or longer than the fourth glume, obtuse, 3- to 5-nerved, paleate, mostly with and rarely without stamens.
The _anthers_ are yellow and they do not open until the stigmas and anthers of the fourth glume are thrown out. _Lodicules_ are two and conspicuous. _Palea_ is hyaline with infolded margins. The _fourth glume_ is coriaceous, broadly ovate, tip acutely pointed and almost cuspidate or acute, mucronate, white or brownish, reticulately minutely pitted. _Anthers_ are three and yellow. _Stigmas_ are purplish.
_Lodicules_ are small but conspicuous.
This gra.s.s is very common throughout the plains and grows in the bunds of paddy fields and in wet situations, and goes up to moderate elevations on the hills. Cattle eat this gra.s.s greedily and seem to like it. It is considered to be an excellent fodder.
_Distribution._--In wet situations all over India ascending to 6,000 feet. Occurs also in Ceylon, Africa, Tropical Asia and Australia.
[Ill.u.s.tration: Fig. 84.--Panic.u.m fluitans.]
=Panic.u.m fluitans, _Retz._=
This is a perennial gra.s.s with prostrate branches which afterwards become erect towards the free ends. The young branches are covered with scale-leaves. Stems are stout, glabrous, smooth and hollow, rooting at the lower nodes.
The _leaf-sheath_ is loose, glabrous, striate, margins not ciliate. The _ligule_ is a ridge with a row of erect long hairs. _Nodes_ are glabrous.
The _leaf-blade_ is firm, linear, finely ac.u.minate, base rounded, rather narrower than the sheath at the white band, very thinly scaberulous above and glabrous below, veins prominent above, 3 to 9 inches long, 1/4 to 7/16 inch broad; margins are slightly incurved and the midrib is conspicuous only at the lower portion of the blade. The scale-leaves persist at the base of the stems.
[Ill.u.s.tration: Fig. 85.--Panic.u.m fluitans.
1 and 2. Front and back view of a spike; 1a. and 2a. front and back view of a spikelet; 3, 4 and 5. first, second and third glume respectively; 5a. palea of the third glume and stamens in it; 6 and 6a. fourth glume and its palea; 7. stamens and ovary.]
The _inflorescence_ is a compound spike varying in length from 4 to 10 inches, erect; the main rachis is triquetrous, dorsally rounded, glabrous and very thinly scaberulous at the edges. _Spikes_ are many (fifteen and more), sessile, secund, generally longer than the internodes, and appressed to the rachis, 1/4 to 1-1/2 inches long; the rachis of the spike is angular, edges scaberulous and with very fine short hairs.
The _spikelets_ are pale, ovoid, acute, biseriate, imbricate, very shortly pedicellate, glabrous, 1/16 to 1/8 inch, pedicels are hairy with a few long hairs towards the base.
There are four _glumes_. The _first glume_ is white, thin, membranous, truncate and wavy at the apex, nerveless or sometimes with one to three short nerves, less than one-third of the third glume, broader than long and clasping at the base. The _second glume_ is ovate, obtuse or subacute, concave, submembranous, slightly shorter than the fourth glume, 5-nerved but occasionally 6- or 7-nerved. The _third glume_ is a little longer than the second and the fourth, usually 5-nerved, broadly ovate, acute, paleate, always with three stamens which come out only after the fading of the stigmas and enlargement of the ovary in the fourth glume. _Lodicules_ are distinct and conspicuous; _palea_ is broad with incurved broad margins and hyaline. The _fourth glume_ is thinly coriaceous, shining, striolate, broadly ovate, mucronate, compressed, faintly and thinly 5-nerved and _palea_ with infolded margins. _Anthers_ are yellow. _Stigmas_ are white when young. _Lodicules_ are distinct.
It is a common gra.s.s of the wet lands met with in many parts of the Presidency and often confused and united with _Panic.u.m punctatum_, Burm.
_Distribution._--Throughout India and Ceylon. It is also found in Arabia, Afghanistan, Africa and Tropical America.
[Ill.u.s.tration: Fig. 86.--Panic.u.m Crus-galli.]
=Panic.u.m Crus-galli, _L._=
It is a tufted annual with many erect branches growing to a height varying from 2 to 3 or 4 feet and the whole plant is glabrous. Stem is stout or slender, simple or branched.
The _leaf-sheath_ is smooth, glabrous and loose, varying in length from 2 to 6 inches, keeled. The _ligule_ is only a smooth semilunar line without hairs. _Nodes_ are glabrous and the lower nodes bear advent.i.tious roots.
The _leaf-blade_ is narrowly linear-lanceolate, flat, finely ac.u.minate, glabrous or very minutely scabrid with a stout midrib; margin is minutely serrate and with tubercle-based hairs near the base. The blades of the lower leaves are longer than those in the upper and at the junction with the sheath the blade is narrow, just as broad or less than the sheath, and becomes broader about the middle; the length varies from 6 to 10 inches generally, also to 14 inches, and breadth at base 1/4 inch and at the middle 5/16 inch; the upper leaf-blade is generally shorter, varying from 5 to 10 inches and very broad at the base near the sheath, about 7/16 inch and gets gradually narrow upwards. It is convolute when young.
The _inflorescence_ is a compound spike varying in length from 4 to 8 inches, contracted and pyramidal and always erect; the main rachis is stout, angled with very minute hairs on the ridges and with a tuft of bristly hairs and also tubercle-based hairs at the place of insertion of the spikes. _Spikes_ are many (up to 16 or rarely more), simple or branched, the lower ones longer, but getting gradually shorter upwards, and varying in length from 1/2 to 2 inches. The rachis of the spike is angular, with scattered tubercle-based bristly hairs.
[Ill.u.s.tration: Fig. 87.--Panic.u.m Crus-galli.
1 and 2. Front and back views of spike; 3. spikelet; 4 and 5. first and second glumes; 6 and 7. third glume and its palea; 8. fourth glume, front and back view; 9. ovary, anthers and lodicules.]
The _spikelets_ are turgid, densely packed on one side of the rachis in three to five rows, sessile or subsessile, sub-globose or ovoid, with unequal tubercle-based bristly hairs on the nerves of the glumes and with short minute hairs on the outer surface of the glumes, 1/12 to 1/8 inch; awn 1/4 inch to 5/16 inch.
There are four _glumes_. The _first glume_ is 1/3 to 1/2 of the third glume, suborbicular, abruptly ac.u.minate or rarely mucronate and 5-nerved (very rarely 5- to 7-nerved), clasping at base and margins thinly ciliolate. The _second glume_ is ovate oblong, short, awned and 5-nerved; sometimes with partial nerves at the apex between the central and the lateral nerves, and then 5- to 7- or 5- to 9-nerved, hispidly hairy on the nerves, margins ciliolate. The _third glume_ is as long as the second, ovate-oblong and the apex abruptly ending in a stout scabrid nerved awn, varying in length from 1/4 to 3/8 inch, rarely 1 inch; 5- to 7-nerved (two partial at tip), paleate and sometimes with three stamens; _palea_ is hyaline, ovate-oblong with infolded margins. The _fourth glume_ is smooth, shining, broadly oblong, faintly 5-nerved, apex rounded or cuspidate with a few cilia; paleate with a single bis.e.xual flower; _palea_ is similar to the glume in structure. _Anthers_ are orange yellow, and _lodicules_ are very small. _Stigmas_ are white.
Grain is smooth and ovoid.
This gra.s.s grows in paddy fields and wet places generally. It is considered to be a very good fodder gra.s.s in Australia and America. This is the "Barn-yard" gra.s.s of the Americans, highly valued as a fodder gra.s.s.
_Distribution._--Throughout India in wet places and in paddy fields.