Fig. 107.—Axonopus cimicinus.
It is a perennial grass. Stems are tufted, erect or slightly decumbent at the base, 1 to 2 feet long.
Theleaf-sheathis distinctly striate, covered with scattered long tubercle-based hairs, very rarely glabrous, keeled. Theliguleconsists of a row of hairs. Thenodesare hairy.
Theleaf-bladeis flat, ovate-lanceolate, broad and cordate at base, subacute or obtuse, with a distinct midrib and three main veins on each side of it, glabrous on both sides, but usually with tubercle-based hairs on the two sides of the midrib, on the lower side, the margins are distinctly ciliate with tubercle-based long stiff hairs and very finely serrate; the blade varies in length from 3/4 to 3 inches and in breadth from 3/4 to 1/2 inch.
Theinflorescenceconsists of three to ten spikes springing from the top of a slender glabrous peduncle 2 to 6 inches long. Thespikesare whorled, about 3 inches or so in length, naked towards the base to about one-fourth of its length, the rachis is fine, filiform, scabrid.
Thespikeletsare solitary or binate, dorsally compressed, pale green or reddish, very shortly pedicelled, 1/4 to 5/16 inch long inclusive of the short awn, pedicel is cupular at the tip.
There are fourglumesin the spikelet. Thefirst glumeis somewhat narrow ovate-lanceolate, hyaline, acuminate and 3-nerved. Thesecond glumeis membranous, ovate-lanceolate, twice as long as thefirst glume, cuspidately acuminate, 5-nerved; the two marginal nerves are provided with long reddish bristly hairs. Thethird glumeis oblong lanceolate, obtuse, 5-nerved, a little shorter than the second glume, paleate and with stamens;paleais short. Thefourth glumeis coriaceous, ovate-lanceolate, nearly as long as the second glume, awned at the apex, paleate, with three stamens and an ovary; thepaleais as long as the glume, elliptic oblong, obtuse.Lodiculesare small, cuneate.
Fig. 108.—Axonopus cimicinus.1. A portion of the spike showing spikelets; 2, 3, 4 and 5. the first, second, third and the fourth glume, respectively; 4a and 5a. the palea of the third and the fourth glume, respectively; 6. lodicules, stamens and the ovary.
This is a common grass growing in the plains and lower hills in waste places.
Distribution.—Occurs all over India.
These are usually annuals. Inflorescence is usually a spike-like panicle. Spikelets are 1- to 2-flowered, jointed on very short pedicels which bear persistent scabrid or barbed bristles (modified branchlets). There are four glumes. The first glume is the shortest, equal to about half the length of the third, membranous, 3- to 5-nerved. The second glume is equal to or shorter than the fourth, 5- to 7-nerved. The third glume more or less exceeding and resembling the second glume, neuter, rarely paleate and male. The fourth glume is coriaceous or crustaceous, plano-convex, bisexual, 5-nerved and paleate; palea is as long as the glume. Lodicules are broadly cuneate. Stamens are three. Stigmas are laterally exserted. Grain is tightly enclosed by the hardened glume and its palea and is oblong or ellipsoid.
KEY TO THE SPECIES.
Bristles with spreading or erect barbs.Inflorescence cylindric, continuous and not interrupted, with six to twelve bristles in the involucel1. S. glauca.Inflorescence interrupted, with three to six bristles in the involucel2. S. intermedia.Bristles with reversed barbs3. S. verticillata.
This is a tufted annual grass. Stems are slender, simple or branched, erect or ascending.
Theleaf-sheathsare glabrous.Nodesare glabrous and sometimes the lower are rooting. Theliguleis a fringe of long hairs.
Theleaf-bladesare lanceolate-linear, flat, finely acuminate, with a rounded base and very finely and minutely serrate margin, glabrous on both the surfaces or occasionally sparsely hairy on the upper surface and varying in length from 4 to 12 inches or more, and in breadth from 1/4 to 1/3 inch.
Theinflorescenceis a cylindric, densely flowered, spike-like raceme, 1 to 4 inches long, usually yellow, rarely purplish or pale green, the bristles of involucels vary from six to twelve and are pale or reddish brown, 1/6 to 1/3 inch long with fine erect or spreading barbs.
Thespikeletsare numerous and are very closely set along the rachis of the inflorescence, 1/8 inch long, glabrous and ellipsoidal.
There are fourglumesin the spikelet. Thefirst glumeis less than half the length of the third glume, broadly ovate, hyaline, 3-nerved. Thesecond glumeis a little longer than the first but shorter than the third, broadly ovate or suborbicular, hyaline, 5-nerved. Thethird glumeis longer than the second, as long as the fourth, membranous and 5-nerved, paleate, empty or with stamens. Thefourth glumeis coriaceous, broadly elliptic, obtuse, dorsally convex, transversely rugose, pale. Theanthersare orange and thestylespurple.
Fig. 109.—Setaria glauca.A and B. spikelets; C. a bristle; 1, 2 and 3. The first, second and the third glume, respectively; 4. palea of the third glume; 5. the fourth glume; 6. palea of the fourth glume; 7. ovary, anthers and lodicules.
This is a fairly common grass especially in cultivated ground all over the Presidency, but not very widely distributed. Cattle are fond of this grass.
Distribution.—Throughout India.
This is an annual with straggling, slender, erect or ascending stems, 2 to 3 feet long.
Theleaf-sheathis glabrous, keeled, with the margins ciliate with long hairs. Theliguleis a fringe of close set long hairs. Thenodesare glabrous and the lower rooting.
Theleaf-bladeis linear-lanceolate, narrowed towards the base, finely acuminate, with fine hairs scattered on both the surfaces and with numerous long hairs at the mouth and with very finely serrate margins, varying in length from 2 to 8 inches or more, 1/8 to 3/4 inch in breadth.
Theinflorescenceis a narrowly pyramidal spike-like panicle, 4 to 6 inches long, the main rachis is glabrous and grooved, branches are short, crowded above, scattered and distant below, with close and densely set spikelets; the bristles of involucels are 1/4 inch long, slender, flexuous with erect barbs varying in number from three to six.
Thespikeletsare ovoid.
There are fourglumesin the spikelet. Thefirst glumeis orbicular, oblong or ovate, about one-third the length of the third glume, hyaline, 3-nerved. Thesecond glumeis half as long as the third, broadly ovate, hyaline, 5-nerved. Thethird glumeis as long as the fourth, broadly ovate, thinly membranous, 5-nerved, paleate, empty. Thefourth glumeis broadly ovate, or suborbicular, very concave, coriaceous, transversely rugulose, yellowish brown.Anthersare orange or yellow andstylespurplish.Lodiculesare very small.
Fig. 110.—Setaria intermedia.1. A branch with spikelets; 2 and 2a. spikelets; 3, 4 and 5. the first, second and the third glume, respectively; 5a. the palea of the third glume; 6. the fourth glume; 6a. the fourth glume and its palea; 6b. palea of the fourth glume; 7. ovary, anthers and lodicules.
Fairly common in rich soils in sheltered places. Cattle are very fond of this grass as the leaves are flaccid and tender.
Distribution.—Probably all over India.
Fig. 111.—Setaria verticillata.
This is an annual grass, with erect, ascending, stout or slender, leafy stems, more or less branched and varying in length from 1 to 5 feet.
Theleaf-sheathsare smooth, glabrous. Theliguleis a fringe of hairs.Nodesare glabrous.
Theleaf-bladesare thin, flat, glabrous, sparsely hairy and scaberulous, linear or linear-lanceolate, tapering to a fine point, base usually narrowed, 4 to 10 inches long and 1/4 to 3/4 inch broad.
Theinflorescenceis a spike-like or subpyramidal panicle, cylindric or oblong, coarsely bristly, 2 to 7 inches long, bristles one or few, studded with conspicuously reversed barbs or teeth, 1/6 to 1/3 inch long.
Thespikeletsare ellipsoidal, obtuse, glabrous, 1/12 inch long.
There are fourglumes. Thefirst glumeis very small, broadly ovate, acute, hyaline, faintly 3-nerved. Thesecond glumeis as long as the spikelet or a little shorter, ovate, subacute, thinly membranous and 5-nerved. Thethird glumeis equal to the second or a little longer, membranous and 5-nerved, paleate or empty, palea when present, is small and hyaline. Thefourth glumeis elliptic-oblong, plano-convex, subobtuse, smooth or shining, though faintly striate, coriaceous with incurved margins;paleais coriaceous, as long as the glume, elliptic, faintly striate.Stamensare three.Lodiculesare small.
Fig. 112.—Setaria verticillata.1 and 2. Spikelets with bristles; 3, 4 and 5. the first, second and the third glume, respectively; 6. palea of the third glume; 7 and 8. the fourth glume and its palea; 9. ovary, stamens and lodicules; 10. a bit of the bristle showing the reversed barbs.
This grass grows in shady places in very rich soils generally and is abundant in shady nooks and corners where there are rubbish heaps.
Distribution.—Throughout India and Ceylon.
These are annual or perennial grasses. Leaves are usually narrow. The inflorescence is a spike-like raceme consisting of involucellate clusters of shortly pedicellate spikelets, involucels consist of unequal, simple or branched bristles. Spikelets are obovoid or lanceolate, 1- to 2-flowered, persistent on their stalks, one to three in an involucel. There are usually four glumes in a spikelet. The first glume is minute or absent. The second glume is shorter than the third, membranous, 3- to 5-nerved, rarely wanting. The third glume is as long as the fourth, lanceolate, paleate or not, male or empty. The fourth glume is coriaceous, lanceolate, bisexual or female. There are three stamens with linear anthers. Styles long. Lodicules are small if present. Grain is oblong, free within the hardened fourth glume and its palea.
KEY TO THE SPECIES
Bristles of the involucel slender and not dilated at the base, and free; leaves very long.1. P. Alopecuros.Bristles of the involucel dilated below and connate at base.2. P. cenchroides.
Fig. 113.—Pennisetum Alopecuros
This is a perennial grass, densely tufted and growing to a height of 2 to 3-1/2 feet. Stems are stout, erect and much branched above.
Theleaf-sheathsare distichous, compressed, glabrous or rarely hairy.
Theleaf-bladesare convolute, narrow, linear, coriaceous, strongly keeled, glabrous but with tufts of soft hairs at the base, 12 to 18 inches long, 1/10 to 1/6 inch broad. Theliguleis a ring of hairs.
Theinflorescenceis a spike-like raceme, varying in length from 5 to 7 inches. The involucels are shortly stalked, with a few unequal bristles which are free down to the base and two to three times as long as the spikelet.
Spikeletsare lanceolate, acute, solitary, 3/8 inch long.
Fig. 114.—Pennisetum Alopecuros.A and B. Spikelets front and back view; 1, 2, 3 and 4. the first, second, third and the fourth glume, respectively; 5. palea of the fourth glume; 6. the ovary, stamens and lodicules.
Thefirst glumeis very small, almost orbicular, hyaline and nerveless. Thesecond glumeis about 1/3 the length of the third glume, lanceolate, acuminate, 3-nerved. Thethird glumeis about 1/3 inch long, lanceolate, acuminate, 7- to 11-nerved, epaleate and with infolded margins. Thefourth glumeis a little longer than the third, lanceolate, acuminate, with infolded margins 5- or 6-nerved, paleate and enclosing a complete flower. Thepaleais lanceolate, acuminate, as long as the glume. There are threestamenswith long, narrow, yellow anthers.Stigmasare feathery.Lodiculesare either absent or very minute.
This is a very coarse grass usually growing in stiff soils especially near wet places.
Distribution.—Occurs all over Southern India both on the plains and on low hills.
Fig. 115.—Pennisetum cenchroides.
This grass is a perennial. It consists of aerial branches and underground rhizomiferous stems, bearing thick fibrous roots and numerous buds covered by scarious sheaths. The aerial branches are tufted, erect or decumbent and geniculately ascending when in flower, much branched from the base, 6 to 24 inches long (under favourable conditions may reach even 3 to 4 feet in length).
Theleaf-sheathis slightly compressed, keeled, with scattered long hairs outside, shorter than the internodes. Theliguleis a short thin membrane fringed with hairs.
Theleaf-bladeis linear, tapering to a very fine point 1-1/2 to 6 inches (sometimes 18 to 20 inches) by 1/8 to 1/4 inch scaberulous with fine long tubercle-based deciduous hairs scattered above, and the lower surface glabrous or with a few distantly scattered fine long hairs, broad at the base and constricted at the point of junction with the sheath.
Theinflorescenceis a raceme of spikes, varying from 1-1/2 to 3-1/2 inches, with the spikes mostly densely arranged, though occasionally distant and not close-set, on a long; slender, puberulous or scaberulous peduncle;rachisis flexuous, flattened, grooved and scaberulous. Thespikeshave involucels, consisting of two series of bristles, the outer bristles are horizontal or reflexed, numerous, fine, filiform, scabrid and purple above, shorter or longer than the spikelets; the inner bristles are two to three times longer than the spikelets, flattened and thickened at the base with a strong green nerve, ciliated with long tubercle-based hairs; one of the bristles is longer than the others and the bases of the bristles are connate at the very base into a ring; the upper portion of the bristles are filiform, scabrid and purple, the lower flattened portion being pale.
Fig. 116.—Pennisetum cenchroides.1. A portion of a spike; 2 and 3. spikelets with their involucels; 4. a bristle; 5, 6, 7 and 8. the first, second, third and the fourth glume, respectively; 7a and 8a. palea of the third and the fourth glume, respectively; 9. ovary and stamens.
Spikeletsare about 1/5 inch long oblong-lanceolate, one to three in a spike and sessile.
There are fourglumesin a spikelet. Thefirst glumeis small, hyaline, ovate-lanceolate, acute, nerveless or sometimes 1-nerved. Thesecond glumeis a little longer than the first, ovate, acute, about half of the third glume, hyaline, 1 to 3-nerved. Thethird glumeis ovate-lanceolate, acuminate, generally 5- to 7-nerved, paleate, usually male;paleais lanceolate, equal to or slightly shorter than the glume. Thefourth glumeis as long as the third with a broad hyaline margin, 5-nerved paleate; palea as long as the glume.Anthersare three, yellow,stigmaswhite, feathery and the styles shortly united at the base.Lodiculesare not present.
This is the famous Kolakattai grass (Tamil) of the Coimbatore District and it grows in all kinds of soil and is capable of growing even when the soil is dry. It is readily eaten by cattle, sheep, goat and when once established is not easily killed out even by prolonged droughts. It is in flower in June, November and December.
Distribution.—Fairly common in South India and Western India. Said to occur in Tropical Africa also.
There is a variety of this grass namedechinoides. This differs from the type in the following respects—the inner bristles are united very much above the base and much thickened and stiffer than in the type. (See fig. 116-3)
The inflorescences are spike-like racemes, consisting of involucellate clusters of shortly pedicelled spikelets jointed on a simple rachis. The involucel consists of hardened spike-like bristles connate at the base into a short coriaceous cup, which is surrounded by erect or squarrose bristles. Spikelets one to three in each involucel, persistent, 1- to 2-flowered, with three or four glumes. The first glume is very small or absent. The second and the third glumes are subequal 5- to 7-nerved. The third glume is longer than the second with male flower or not, paleate. The fourth glume is coriaceous, with a bisexual or female flower. Lodicules are two. Stamens are three. Styles are long, free or connate below. Grain is broad, oblong and compressed.
KEY TO THE SPECIES
Base of involucel rounded; inner bristles shorter, erect, not ciliateand connate at base.1. C. biflorus.Base of involucel turbinate, inner bristles longer, spreading and spinescent, ciliate at base2. C. catharticus.
This is an annual with erect simple stems, 6 to 24 inches long.
Theleaf-sheathis glabrous or nearly so, with hairs at the mouth.
Theleaf-bladeis linear-lanceolate, finely acuminate, glabrous or hairy, 3 to 10 inches long and 1/8 to 3/8 inch broad.
Theinflorescenceis a solitary cylindric raceme of involucels, 2 to 4 inches long, enclosed in the uppermost leaf-sheath; therachisis flexuous, angular and smooth.Involucelsusually with two, rarely three spikelets, loosely imbricate, rounded at the base; the inner bristles are erect, dorsally flat, subulate-lanceolate, puberulous and with thickened margins, about 1/8 inch long. The outer are shorter than the inner, glabrous, erect or subsquarrose and as long as the sessile spikelets.
Thespikeletsare about 1/6 inch long, sub-globose, with fourglumes. Thefirst glumeis about 1/10 inch long, ovate-acuminate, very thin, hyaline, nerveless or rarely 1-nerved. Thesecond glumeis broadly ovate, 1/6 inch long, hyaline, acute, 1-nerved. Thethird glumeis slightly longer than the second, oblong-ovate, apiculate, 5-nerved and paleate;palea1/8 inch obtuse. Thefourth glumeis as long as the third, ovate, obtuse, paleate.Anthersare three.Stylesfree almost to the base. The grain is 1/12 by 1/16 inch orbicular oblong, compressed, smooth and pale brown.
Fig. 117.—Cenchrus biflorus.1. A portion of the raceme; 2. an involucel; 3, 4, 5 and 7. the first, second, third and the fourth glume respectively; 6 and 8. palea of the third and the fourth glumes; 9. the ovary and stamens; 10 grain.
This grass is not so widely distributed asCenchrus catharticus. It is confined to some East Coast districts.
Distribution.—The Punjab, Gangetic plain, Concan, Sind and Coromandel. Also said to occur in Africa and Arabia.
A tufted annual grass with geniculately ascending stems, branching at the base.
Theleaf-sheathis glabrous and somewhat inflated. Theliguleis a fringe of hairs.Nodesare glabrous.
Theleaf-bladeis linear-lanceolate, finely acuminate, 1 to 4 inches long and 1/8 to 1/4 inch broad.
Theinflorescenceis usually enclosed in the leaf-sheath, 1 to 6 inches long; therachisis flexuous, angular and glabrous. The involucels are 1/4 to 1/2 inch across, turbinate or truncate at base with an outer, shorter and inner longer series of hard, sharp, pungent spines; the inner subulate, dorsally deeply grooved, very much longer than the spikelets; margins ciliate to about half the distance from the base, and the upper half covered with very short, sharp and stiff, reflexed hairs; the outer are shorter than the spikelets, spreading or erect, glabrous or nearly so and covered with reflexed hairs.
Thespikeletsare usually one to two and rarely three in an involucel and each one has fourglumes. Thefirst glumeis lanceolate and nerveless or ovate-lanceolate and 1-nerved, half as long as the third glume, hyaline and acute. Thesecond glumeis about 1/6 inch long, ovate, acute, membranous, 5-nerved. Thethird glumeis similar to the second, paleate;paleais lanceolate and short. Thefourth glumeis as long as the third, cuspidately acuminate, membranous, 5-nerved and paleate;paleais ovate, as long as the glume.Stamensare three.Stylesare free and long with plumose stigmas. The grain is ovoid-oblong, brown and compressed.
Fig. 118.—Cenchrus catharticus.1. A portion of the spike; 2. an involucel with two spikelets; 3, 4, 5 and 7. the first, second, third and the fourth glume respectively; 6 and 8. palea of the third and the fourth glume respectively; 9. the ovary and stamens; 10. grain.
This grass is more common thanC. biflorusand is found on the East Coast districts in open sandy places.
Distribution.—Nellore, Bellary, the Punjab and the Gangetic Plains.
Oryzeæis a very small tribe with a few genera, which usually flourish in marshes. The spikelets are in panicles, 1-flowered and the flower is usually perfect. In Oryza there are three glumes, the first two being very minute, and there is only a single glume in Leersia and Hygrorhiza. There are usually six stamens. The palea becomes firm in texture like the glume instead of remaining hyaline, and so it is often mistaken for a glume. The spikelets are jointed on their pedicels and fall away from them.
Not floating; spikelet not awned11. Leersia.Floating; spikelets awned12. Hygrorhiza.
Zoysieæis another small tribe with half a dozen genera. The inflorescence is either a spike-like raceme or a spiciform panicle. The spikelets are solitary in Perotis, binate in Tragus and grouped in Trachys. There is usually a complete flower in a spikelet and the glumes are membranous. Mature spikelets are deciduous with their pedicels singly in Perotis and in clusters in others.
Spikelets fascicled unilaterally on a broad rachis, 4-glumed, glumes not echinate13. Trachys.Spikelets binate and all round the rachis, 3-glumed, glumes echinate14. Tragus.Spikelets single, awned and 3-glumed15. Perotis.
These are tall perennial marsh grasses. The inflorescence is usually a more or less contracted panicle with very slender branches. The spikelets are compressed and consist of only one glume bearing a perfect flower. The solitary flowering glume is chartaceous, awnless, 3- to 5-nerved, the lateral nerves forming the thickened margin of the glume. The palea is narrow, linear-lanceolate, as long as the glume, 3-nerved, rigid, dorsally ciliate, and with hyaline margins. Lodicules are two. Stamens are usually six in number. Styles are short, with plumose stigmas and laterally exserted. Grain is ovoid or oblong, compressed, free within the glume and its palea.
This is a slender perennial marsh-grass with stems rooting in the mud and with flexuous floating branches, sending up erect or ascending, weak and slender leafy branches, 2 to 4 feet high.
Fig. 119.—Leersia hexandra.1. Erect branch; 2 and 3. bits of leaves with ligules; 4 and 5. spikelets; 6. ovary and lodicules.
Theleaf-sheathis smooth, glabrous, with eciliate margins. Theliguleis a short obliquely truncate or two-lobed membrane.Nodesare hairy with deflexed hairs.
Theleaf-bladeis flat, narrow, linear, tapering to a fine point, suberect and rather rigid, glabrous and with a narrow base, varying in length from 3 to 10 inches and 1/8 to 1/3 inch in breadth.
Theinflorescenceis an oblong laxly branched, narrow pedunculate panicle, 2 to 4 inches long.
Thespikeletsare all 1-flowered and 1-glumed, articulate on the pedicels above the rudimentary glumes, strongly laterally compressed. Theglumeis about 1/6 inch long, ovate-oblong, somewhat boat-shaped, acute and shortly mucronate, strongly keeled, ciliate on the keel and margins, 5-nerved, the lateral nerves forming a thickened margin;paleais as long as the glume, linear-lanceolate, subacute, rigid with membranous margins.Stamensare six and there are two smalllodicules. The first two glumes are reduced to an obscure hyaline rim.
This marsh-grass is found in marshy places such as ditches and channels in paddy fields, ponds and tanks.
Distribution.—It is found all over India and Ceylon; also in Africa, America and Australia.
These are floating glabrous grasses with stems diffusely branching and profusely rooting at the nodes. The inflorescence is a panicle. The spikelets are 1-flowered, with a solitary flowering glume only. The flowering glume is awned, strongly 5-nerved, nerves scabrid and ciliate, the lateral nerves being marginal. Palea is 3-nerved, narrow acuminate with a ciliate keel. Lodicules are suborbicular. There are six stamens with long slender anthers. Styles are free with plumose stigmas, laterally exserted. Grain is oblong, narrowed at the base, obtuse, free within the glume and its palea.
This is a floating aquatic grass. Stems are spongy, branching diffusely, 1 foot long, with feathery whorled roots in dense masses at the nodes; branches are short, erect and leafy.
Theleaf-sheathis smooth, inflated, compressed, with ciliate margins. Theliguleis a narrow membrane.Nodeshave whorls of roots.
Theleaf-bladeis linear or ovate-lanceolate, obtuse, glabrous, glaucous beneath, base rounded or subcordate, 1 to 3 inches long and 1/2 to 3/4 inch broad.
Theinflorescenceis a panicle, 2 inches long and broad, somewhat triangular in outline; therachisand the branches are stiff, slender and smooth, the lower branches are a little deflexed.
Fig. 120.—Hygrorhiza aristata.1. Branch; 2. part of a leaf with ligule; 3. spikelet; 4 and 5. glume and its palea; 6. lodicules and ovary.
Thespikeletsare very narrow, sessile or pedicellate, articulated on the pedicel, 1-flowered and 1-glumed. Theglumeis about 3/8 inch long (excluding the awn) and the awn is as long as the glume or slightly longer, lanceolate, with five strong nerves and the lateral ones forming thickened margins; the palea is as long as the glume.Stamensare six andlodiculestwo.
Found in ponds and tanks.
Distribution.—All over India and Ceylon.
These are softly, villous, diffuse annual grasses. The inflorescence consists of usually two (rarely three) divaricating spikes on a long peduncle. The rachis is herbaceous, broad flexuous, jointed and bearing at each joint a solitary globose cluster of two or three perfect 1-flowered glabrous spikelets surrounded by many short spinescent glumes of imperfect ones. The perfect spikelets are 4-glumed and the glumes are very unequal. The first glume is minute, tooth-like, nerveless. The second glume is long, linear-lanceolate, membranous, very acute, strongly 3- to 5-nerved. The third glume is the largest, obliquely ovate, or obovate-oblong, cuspidately acuminate, rigidly coriaceous, 9- to many-nerved, paleate or not, empty. The fourth glume is shorter and narrower than the lower one, linear-oblong, acuminate, chartaceous, smooth, dorsally convex, with incurved margins, bearing a bisexual flower, paleate, palea is hyaline as long as the glume, and the margins are inflexed below the middle. Lodicules are very minute or wanting. There are three stamens. The styles are very long with slender stigmas, exserted at the top of the glume. The grain is oblong, compressed, free within the glume and its palea.
This is a diffusely branching, softly villous annual grass. The stems are many from the root, 16 to 18 inches long, ascending or decumbent and prostrate, leafy, glabrous, rooting freely at the lower nodes, especially when procumbent.
Theleaf-sheathsare loose, inflated, hairy or rarely glabrous. Theliguleis a thin membrane, or a ridge of fine closely set hairs.Nodesare villous.
Theleaf-bladeis linear-lanceolate to ovate-lanceolate acuminate, flaccid, softly villous on both the surfaces, margins often crisped, base rounded, 2 to 6 inches by 1/4 to 1/2 inch.
Theinflorescenceconsists of a long or short, slender, shining peduncle bearing two or three rigid, flattened, flexuous, jointed spikes, the rachis is broad, herbaceous, with a flat, broad, closely nerved wing on both the sides and with a distinct flat midrib and jointed, each joint bears on the under surface at the articulation, a solitary, globose cluster of two to three perfect 1-flowered glabrous spikelets surrounded by many short spinescent glumes of imperfect ones. The spikes vary in length from 1 to 2 inches and in breadth from 1/10 to 1/6 inch and are glabrous.
The clusters ofspikeletsare about 1/4 inch in diameter, often partially sunk, in a concavity of the rachis; the perfect spikelets are 1/5 to 1/4 inch long and the imperfect are shorter.
Fig. 121.—Trachys mucronata.A and B. The spikelets; 1, 2 and 3. the first, second and the third glume, respectively; 4. palea of the third glume; 5 and 6. the fourth glume and its palea; 7. lodicules, ovary and stamens.
In the perfect spikelet there are four very unequal glumes. Thefirst glumeis minute, tooth-like, triangular or lanceolate, acute, nerveless, 1/16 to 1/12 inch long. Thesecond glumeis elongate, linear-lanceolate, acute, sometimes ciliate below the middle, membranous, narrower than the third glume, hyaline, strongly 3-nerved, 1/16 by 1/6 inch. Thethird glumeis 1/5 by 1/8 inch the largest in the spikelet, broadly and obliquely ovate or obovate,cuspidately acute, with nine to many green nerves, paleate; thepaleais very small, about 1/20 inch long, oblong, hyaline and rigidly coriaceous. Thefourth glumeis much narrower and shorter than the third glume, linear oblong, acuminate, chartaceous, smooth, dorsally convex, with incurved margins, bisexual and paleate; the palea is as long as the glume, acuminate, hyaline, the margins inflexed below the middle, ovate, acute.Lodiculesare minute or absent.Stamensare three with linear anthers.Stylesare very long with slender stigmas. The grain is oblong, compressed.
This grass grows abundantly in cultivated dry fields and in the sand near the sea-shore and it is easily recognized by the clusters of spikelets in the spike.
Distribution.—The Deccan Peninsula—both in the interior and on the sea coast.
These are annual or perennial grasses, with erect or prostrate stems. Inflorescence is a spiciform raceme, bearing the spikelets in clusters of 2 to 4. The spikelets are 1-flowered and usually with two glumes. Sometimes a very minute hyaline lower glume is present. The first glume is thickly coriaceous, 5-ribbed, oblong-lanceolate, and ribs with long recurved spines. The second glume is oblong or oblong-lanceolate, apiculate, chartaceous, 3-nerved and with a perfect flower; palea is as long as the glume, 2-nerved. Lodicules are broad, cuneate and fleshy. There are three stamens. Styles are slender and distinct, with narrow stigmas exserted from the top of the glume. Grain is oblong to ellipsoidal free within the glume and its palea.
Fig. 122.—Tragus racemosus.
This plant is a perennial with tufted prostrate or erect stems, rooting at the nodes freely and densely leafy. The flowering branches are erect or geniculately ascending and varies from a few inches to about a foot.
Theleaf-sheathis short, pale, glabrous, somewhat compressed, striate, equitant below and upper are longer, terete and green. Theliguleis only a ridge of short, fine hairs.Nodesare glabrous.
Theleaf-bladeis convolute when young, ovate or ovate-lanceolate, variable from 1/4 to 2 inches long and 1/10 to 1/6 inch wide, acuminate, flat or somewhat wavy, glabrous on both the surfaces, rigidly pungent, densely crowded and distichously imbricate in the lower part of the stem, base is amplexicaul, and the margin is distantly serrate and rigidly ciliate.
Theinflorescenceis a spike-like terminal panicle varying in length from 3/4 to 2 inches; therachisis wavy, slender, angular or grooved, pubescent, the peduncle is striate, pubescent and enclosed by the leaf-sheath.
Thespikeletsare arranged in groups of two, facing each other and appearing like a single spikelet with two equal echinate glumes, sessile, or obscurely pedicelled on very short, tumid, pubescent branches.
Fig. 123.—Tragus racemosus.1. A pair of spikelets; 2, 3 and 4. the first, second and the third glume, respectively; 5. palea of the third glume; 6. ovary, anthers and lodicules.
There are two (rarely three)glumesin the spikelet. Thefirst glumeis very minute, hyaline, obtuse and it is very often not present. Thesecond glumeis about 1/8 inch, ovate-lanceolate, acuminate, strongly 3-ribbed with rows of stout, spreading hooked spines along the ribs and encloses a single floret. The margins of this glume are membranous and somewhat scaberulous. Thethird glumeis about 1/12 inch, oblong lanceolate, membranous minutely hairy, 3-nerved and finely pointed at the apex; thepaleais as long as the glume, hyaline, 2-nerved, lanceolate, subacute and irregularly toothed at the apex.Stamensare three, with slenderfilaments, anthers are short, broad and pale yellow. The style branches are pale and feathery.Lodiculesare two, fleshy and cuneate or subquadrate. The grain is free inside the glume and the palea, linear oblong, slightly compressed and pale brown, the embryo occupies about 1/3 the length of the grain.
This is one of the commonest grasses growing everywhere in tufts with usually prostrate branches. In some situations the branches are erect.
Distribution.—Plains of India throughout and Ceylon. It is found in all the warm regions of the world.
These are slender annual or perennial grasses with short broad leaves. Inflorescence is a spike or spiciform raceme. The spikelets are 1-flowered, sessile or shortly pedicelled and jointed. There are three glumes in the spikelet. The first and the second glumes are empty, subequal, narrowly linear with a strong midrib which is produced into a long capillary awn. The third glume is very small, hyaline, lanceolate, acute, 1-nerved and with a perfect flower; palea is small, narrow, hyaline and nerveless. Stamens are three with short anthers. Styles are short and united at the base with very short stigmas. The grain is long and narrow, longer than the flowering glume.
Fig. 124.—Perotis latifolia.
This grass is an annual with slender leafy stems, branching at the base, prostrate at first and then geniculately ascending, terminating in inflorescences and varying in length from 3 to 15 inches.
Theleaf-sheathsare glabrous, usually all short except the one next to the inflorescence which is two or three times as long as the lower sheaths. Thenodesare purple and glabrous.
Theleaf-bladeis short, 1 to 1-1/4 inches long, ovate or lanceolate, cordate at base, acute and glabrous on both the surfaces; the margin is minutely serrate, rigidly ciliate and with a very narrow hyaline border.
Theinflorescenceis a slender, crinite, spike-like raceme, 1 to 8 inches long, with a finely scabrid mainrachis.
Thespikeletsare narrow linear 1/12 to 1/8 inch or longer, purple, shortly pedicelled and 1-flowered, pedicels are short with a hyaline swelling on the upper side at the base.