In Flora of British India, this plant is included under Sporobolus coromandelia.n.u.s. These two plants (_S. coromandelia.n.u.s_ and _S.
commutatus_) are quite distinct and grow side by side. As the differences are not easily seen in herbarium specimens the two plants are put together under the one species _S. coromandelia.n.u.s_. The branches are tufted and are usually dec.u.mbent at base, leaves quite green and somewhat broad in _S. coromandelia.n.u.s_; and in _S.
commutatus_, branches are usually not dec.u.mbent at base, generally erect from the base and leaves are green glaucous and somewhat narrow. The most striking difference, however, is in the panicle. The branches of the panicle are always stiff and horizontal in S. coromandelia.n.u.s and the spikelets are appressed to the branches and never spreading or drooping, whereas in _S. commutatus_ the branches are never stiff and horizontal, always obliquely ascending and the spikelets are spreading and drooping. Judging from living plants these two are undoubtedly distinct and so this plant is treated as a distinct species retaining Kunth"s name _Sporobolus commutatus_. Enumeratio Plantarum, Pl. I, 214.
_Distribution._--This occurs in Coimbatore, Madras and Bellary Districts; but it is not so common nor so widely distributed as S.
coromandelia.n.u.s, _L._
[Ill.u.s.tration: Fig. 185.--Sporobolus scabrifolius.]
=Sporobolus scabrifolius, _Bhide._=
The plant is a very pretty one, especially when in flower. It is a loosely tufted annual varying in height from 5 to 30 inches. Stems are slender, terete, 6 to 30 inches long, bent at the base, then geniculately ascending and finally becoming erect, glabrous, pale green or purplish.
The _leaf-sheath_ is shorter than the internode, slightly compressed, obscurely keeled, glabrous and striate, margin is thinly ciliate on one side, especially towards the mouth which is bearded. The leaf-sheath embracing the peduncle is longer than the lower sheaths. The _ligule_ is a fringe of close-set hairs on an inconspicuous ridge. The _nodes_ are glabrous.
The _leaf-blade_ is glaucous green, 1 to 5 inches long, 1/8 to 3/8 inch broad, linear-lanceolate or lanceolate, ac.u.minate, flat, rounded or subcordate, and amplexicaul at base, scaberulous throughout, with tubercle-based deciduous hairs on both the surfaces, and bearded at the base above the ligule; the margin is thickened, serrulate, ciliate with bulbous-based deciduous hairs.
[Ill.u.s.tration: Fig. 186.--Sporobolus scabrifolius.
1. Portion of a branch; 2. spikelet; 3, 4 and 5. the first, second and third glumes; 6. palea; 7. anthers and ovary; 8. grain.]
The _inflorescence_ is an effuse panicle, 2-1/2 to 7 inches long and 1 to 4-1/2 inches broad, pyramidal or elliptic on a slender peduncle 1 to 7 inches long; _rachis_ is striolate, cylindric, glabrous and partly green and partly purplish. Branches are capillary, 1/2 to 2-1/2 inches long, those in the middle of the panicle are often the longest pale green at first but turning purple later, whorled regularly or irregularly, with often a solitary or twin branches intervening, spreading, horizontal, reflexed, rarely one or two erect, dividing into still finer branchlets below, ending in a few solitary spikelets above, swollen at the base near the place of insertion and naked to a short length, scabrid. The lowest whorl consists of five to ten branches and in others they vary from three to eight; the branchlets are spreading and drooping bearing from two to seven spikelets. There are glandular streaks at the base of the branches above the point of insertion in the naked portion and also on the pedicels of the spikelets.
_The spikelets_ are 1/20 to 1/16 inch long, lanceolate, ac.u.minate, on finely capillary pedicels long or short, pale at first and becoming purplish when old. There are three _glumes_, the first two being empty.
All the glumes are 1-nerved and membranous. The _first glume_ is membranous, about two-thirds of the second, sometimes less, ovate-lanceolate, ac.u.minate slightly scaberulous on the keel. The _second glume_ is a little longer than the third, ovate-lanceolate, ac.u.minate, scaberulous on the keel. The _third glume_ is oblong-ovate, glabrous, flower bearing, paleate; the _palea_ is shorter than the glume, 2-nerved, splitting into two between the nerves. _Anthers_ are three, small, pale yellow at first but becoming purple when old, _stigmas_ are pale. _Lodicules_ are two and minute. Grain is rounded, slightly compressed, oblique at the base, nearly as long as broad.
_Distribution._--In black cotton soils in Coimbatore and Bellary districts.
33. Gracilea, _Koen._
These are small tufted gra.s.ses. The inflorescence is a spike bearing unilaterally turbinate cl.u.s.ters of spikelets which are 2-flowered. The spikelets have usually four, and rarely six glumes and very often the rachilla is produced beyond the fourth glume. The first and the second glumes are narrow (the first being the narrowest), rigid, ciliate with long hairs and awned. The third glume is bis.e.xual, chartaceous, broadly ovate, 3-nerved, shortly awned. The fourth glume is similar to the third but smaller and male. The fifth and sixth glumes when present are small and empty. Lodicules are two and small. Grain linear oblong.
KEY TO THE SPECIES.
Stems stout; leaves not filiform; tip of glume III entire 1. G. nutans.
Stems slender, leaves filiform; tip of glume III toothed 2. G. Royleana.
=Gracilea nutans, _Koen._=
This gra.s.s is a perennial with stout fibrous roots. Stems are stout, leafy and creeping below, ascending later; naked and slender above, 4 to 10 inches long.
The _leaf-sheath_ is glabrous, shorter than the blade, coriaceous and open above. The _ligule_ is a ridge of hairs.
The _leaf-blade_ is lanceolate, narrowed from the rounded or subcordate base to the acute tip, coriaceous, 3/4 to 1 inch long; margins are ciliate with tubercle-based cilia; the surfaces with or without a few scattered long tubercle-based hairs.
The _inflorescence_ is 1 to 3 inches long, consisting of distant sessile fascicles of four to six spikelets; the _rachis_ of the spike is flexuous; the _rachis_ of the fascicles ends in three subulate empty glumes.
[Ill.u.s.tration: Fig. 187.--Gracilea nutans.
1. A portion of the inflorescence with three fascicles of spikelets; 2.
a spikelet without the first glume; 3, 4, 5 and 8. the first, second, third and the fourth glume, respectively; 6 and 10. palea of the third and the fourth glume, respectively; 7. lodicules, stamens and the ovary; 9. the rachilla produced beyond the fourth glume.]
The _spikelets_ are closely appressed and each one has four _glumes_.
The _first_ and the _second glumes_ are empty, 2/5 inch long, rigidly coriaceous, gradually narrowed from a villous base into an erect, scabrid awn, 1-nerved. The _second glume_ has broad hyaline margins towards the base. The _third glume_ is about 1/10 inch, ovate, with a short scabrid awn at the tip, scaberulous at the back just above the middle, 3-nerved, paleate and with both stamens and ovary; _palea_ is narrow, lanceolate, as long as the glume and 2-toothed at the tip. The grain is oblong, brownish. The _fourth glume_ is about half as long as the third glume, with a short, stout, smooth rachilla, ovate-lanceolate, terminated at the tip by two teeth and a short awn, scabrid above the middle at the back, paleate and male; _palea_ is shorter than the glume; the rachilla is produced beyond the fourth glume and terminates in a thickening.
This gra.s.s grows in open somewhat dry loamy and laterite soils in the East Coast districts.
_Distribution._--Mysore and the Carnatic and Ceylon.
=Gracilea Royleana, _Hook. f._=
This is a slender annual gra.s.s. Stems are very slender, densely tufted, geniculately ascending or erect, 3 to 8 inches long.
The _leaf-sheath_ is either covered with scattered tubercle-based hairs or glabrous. The _ligule_ is a hairy ridge. The _nodes_ are glabrous.
The _leaf-blade_ is filiform, linear-lanceolate, acutely pointed, glabrous or nearly so, margins distantly ciliate, 1 to 2 inches long by 1/16 inch or less.
The _inflorescence_ is 1/2 to 3 inches long and consists of fascicles of spikelets; the rachis is trigonous, smooth, and flexuous.
[Ill.u.s.tration: Fig. 188.--Gracilea Royleana.
1. A fascicle of spikelets; 2. the spikelet without the first and the second glumes; 3,4, 5 and 8. the first, second, third and the fourth glume, respectively; 6. palea of third glume; 7. grain; 9. palea of the fourth glume; 10. rachilla.]
The _spikelets_ consist of four _glumes_. The _first glume_ is rigidly coriaceous, gradually narrowed from a villous base to an erect scabrid awn, 1-nerved. The _second glume_ is also coriaceous, narrowed to an awn but has broad hyaline margins towards the base. The _third glume_ is ovate-lanceolate, scabrid all over the back and with two teeth, one on each side of the awn, paleate; the _palea_ is 2-toothed at the apex and as long as the glume and contains three stamens and the ovary. The grain is oblong brownish. The _fourth glume_ is stalked, shorter than the third glume, distinctly 3-toothed at the apex, scabrid at the back above the middle, paleate and male; the _palea_ is smaller than the glume and 2-toothed at the apex. The _rachilla_ is produced behind the palea and it ends in two small teeth, one being slightly larger than the other.
This gra.s.s is a very slender one and it is closely allied to _Gracilea nutans_. It differs from _G. nutans_ in being an annual and in having filiform leaves, bicuspidate third glume which is scabrid all over the back and a fourth glume distinctly tricuspidate at the apex. This does not occur so widely as _Gracilea nutans_.
_Distribution._--Bellary and Chingleput districts, the Punjab, Rajputana, Concan and Kanara.
34. Enteropogon, _Nees._
Tall slender gra.s.ses with very long narrow leaves. Spikelets are 2-flowered, narrow, biseriate, unilateral, imbricate on the rachis of a solitary spike; the rachilla is elongate between the flowering glumes and produced beyond them and terminates in a rudimentary awned glume.
There are four glumes. The first two glumes are hyaline, unequal-nerved and persistent. The third and the fourth glumes are chartaceous, narrowly lanceolate, 3-nerved, bicuspidate and awned below the tip; awns are capillary, straight; the callus is bearded and articulate at the base. The third glume bears a bis.e.xual or female flower and the fourth bis.e.xual or male. Lodicules are two. Stamens are three with long anthers. Styles short diverging from the base, with short stigmas laterally exserted.
=Enteropogon melicoides, _Nees._=
This is a tall perennial gra.s.s with stout roots. Stems are densely tufted on a short woody root-stock, erect, leafy, 1 to 3 feet long.
_Leaf-sheaths_ are compressed and distichous below, glabrous or sometimes with a few hairs close to the margin. Ligule is a ridge with long hairs.
The _leaf-blade_ is very long 1/6 to 1/4 inch broad, auricled at the base, narrowed into very finely ac.u.minate or capillary tips midrib prominent; scaberulous on both the surfaces and with long hairs on the auricles.