Fig. 137.—Ischæmum laxum.
1. A sessile and a pedicelled spikelet; 2. first glume of a sessile spikelet; 3. second glume of a sessile spikelet; 4 and 5. third and fourth glumes of sessile spikelets; 4a and 5a. are palea of third and fourth glumes; 6. ovary; 7, 8, 9 and 10. glumes of pedicelled spikelets; 9a and 10a. palea of third and fourth glumes.
The spikelets are in pairs, one-sessile and one-pedicelled. The sessile spikelets are pale-green, linear-oblong, acuminate with a shortly bearded callus, 1/4 to 3/8 of an inch long. There are four glumes in a spikelet. The first glume is chartaceous, oblong-lanceolate, acuminate, 2-toothed with the teeth ending in two short awns, densely ciliated at the apex on one side, conspicuously 6- (rarely) 7-nerved, the two lateral being very strong and running into the apical teeth and the intermediate four nerves being shorter and not running up to the apex, and on the dorsal surface there is a depression, where it is membranous and the nerves on its sides sometimes anastomosing at the upper third of the glume. The second glume is shorter than the first, chartaceous to a certain extent, ovate-lanceolate, acuminate, concave, terminating in a fine scabrid awn, 1/2 inch long, with margins ciliate from above the middle to the apex, and with a narrow ciliated wing on the keel at the apex running up to the base of the awn, 3-nerved. The third glume is lanceolate, acuminate, hyaline, nerveless, ciliate, with a linear obtuse palea enclosing three stamens and two lodicules. The fourth glume is hyaline, membranous, deeply split at the apex into two prominent lobes and with an awn in the depression 1/2 inch long, the palea is linear oblong and contains either the ovary alone or both the stamens and the ovary.
The pedicelled spikelets are also as long as the sessile, more conspicuous than the sessile and consist of four glumes, but are not awned. The first glume is lanceolate or oblong-lanceolate, chartaceous, with seven strong nerves, very prominent at the back and the mid nerve being most conspicuous, with scabrid keels and closely finely ciliated and folded margins, finely biaristate at the apex. The second glume is lanceolate, finely acuminate, sub-chartaceous, with the margins ciliate from about two-third its length from the apex, 3-nerved, the mid nerve alone being prominent. The third glume is hyaline, nerveless, lanceolate, ciliate in the margin, paleate with 3 stamens or empty. The fourth glume is shorter than the third, hyaline, narrow lanceolate, not awned, ciliate or not at the margin, paleate and with three stamens and two lodicules.
This grass produces a large amount of leaves in good soils and it is liked very much by cattle. It is capable of standing a long spell of dry weather, and is valuable in this respect because it can be depended upon when other grasses fail. It is worth conserving with other grasses. It grows both in rich and poor soils, in open places and also in thickets.
Distribution.—Throughout India and Ceylon.
21. Eremochloa, Buse.
These are tufted perennial grasses with rigid equitant leaves at the base. The inflorescence consists of a solitary, glabrous, and compressed spike, with a somewhat fragile rachis; the joints are compressed, hollow and clavate. The spikelets are solitary, usually 2-flowered (rarely 1-flowered), secund, closely imbricating, sessile with a short, pedicelled, reduced upper spikelet, and deciduous with the joint. There are four glumes. The first glume is oblong or ovate, flat, smooth, coriaceous, pectinately margined with upcurved spines. The second glume is oblong-lanceolate, acute and 3-nerved. The third glume is hyaline, obtuse, paleate and male. The fourth glume is smaller, hyaline, oblong, obtuse, 1-nerved, paleate, bisexual or female. Lodicules are truncate and slightly oblique. Stamens are three with long anthers. Styles are two with feathery stigmas. The grain is oval, plano-convex.