4. Andropogoneæ. Saccharum (Sugar-cane); the spikelets are exceptionally small, 1-flowered, and borne in pairs in many-flowered, long-haired panicles. Tall grasses with solid, sappy stem.—Andropogon.
5. Festuceæ. Grasses with panicle (or spike-like panicle) and 2–several-flowered spikelets. Glumes small, in each case shorter than the spikelet.—Festuca (Fescue) and Bromus (Brome, Fig. [288]) have the awn placed at the apex of the pale, or slightly below it. Festuca has perennial species, with only a sparsely-branched panicle with branches solitary or in pairs, and round spikelets; the leaf-sheath is widely open. Bromus has the branches borne in half whorls, and the leaf-sheath scarcely half open. Brachypodium has very short-stalked spikelets in a raceme.—Poa (Meadow-grass), Briza (Quaking-grass) and Glyceria have awnless spikelets; these in Poa are ovoid, compressed, and with sharply-keeled glumes; in Briza they are broad, cordate and drooping, with boat-shaped glumes; in Glyceria round, long, many-flowered, linear or lanceolate; some species of Glyceria have closed leaf-sheaths.—Dactylis (Cock’s-foot) differs from all others in the somewhat crowded and unilateral (subsecund) spikelets, which are compressed and oblique (i.e. one side more convex than the other).—Phragmites (P. communis, Reed); the lowermost flowers of the spikelet are ♂; its axis is covered with long, silky hairs; pales without awns, but acuminate. Perennial marsh-plants.—Melica; panicle small, sparsely-branched with round, awnless, few-flowered, usually drooping spikelets. The upper pales, with arrested flowers, are generally united into a club-like mass.—Molinia, Eragrostis, Koeleria, Catabrosa.—Cynosurus (Dog’s-tail) has a small, spicate panicle with unilateral spikelets, some of which are fertile, some barren, each supported by a pectinate scale. Arundo. Sesleria. Gynerium. Triodia.
6. Aveneæ. Panicles with 2–many-flowered spikelets; at least one of the glumes is quite as long as the entire spikelet.—Avena (Oat). The pale is boat-shaped, often bifid, and at about the middle of the back has a twisted, bent awn.—Aira (Hair-grass) has a long-branched panicle with small, 2-flowered spikelets; the pale has a dentate apex and bears an awn on the posterior side close to the base.—Weingærtneria.—Holcus (Yorkshire-fog); a soft, hairy Grass with an open panicle, keeled glumes; 2 flowers in the spikelet, of which the lower one is ☿, the upper ♂; the pale which supports the ☿-flower has no awn, but that which supports the ♂-flower, on the contrary, is awned.
7. Agrostideæ. Panicles or spike-like panicles with 1-flowered spikelets. Generally 2 glumes and only 1 pale.—The following have PANICLES: Milium with square panicle-branches and round spikelets; Agrostis (Fiorin), with compressed, glabrous spikelets, whose glumes are longer than the pales. Calamagrostis differs in having a chaplet of long hairs at the base of the pale.—Stipa (Feather-grass) has a long, twisted awn.—The following have SPIKELIKE PANICLES: Phleum (Cat’s-tail, Timothy-grass) has sharply pointed, entirely free glumes, which are much longer than the awnless pales. Alopecurus (Fox-tail); glumes united below; pale with awn. Ammophila (Psamma). A. arundinacea; pales hairy at base; perennial, stiff-leaved, glaucous sand-grass with creeping rhizome. Aristida. Sporobolus.
8. Phalarideæ. Panicles and spike-like panicles. The spikelet has in the upper part a single fertile flower; below it are placed 4 pales, of which the upper 1–2 sometimes support ♂-flowers. On the whole, 6 floral-leaves of the first order are present.—Phalaris (P. canariensis, Canary-grass) has an ovate, spike-like panicle, the spikelets are compressed, convex on the outer side, concave on the inner. The large glumes are winged on the back.—Digraphis (D. arundinacea) is closely allied to Phalaris, but the keel of the glumes is not winged.—Anthoxanthum (A. odoratum, Sweet-vernal) has a small, lanceolate, open, spike-like panicle; the spikelets have below 2 barren flowers, and above these an ☿-flower with 2 stamens. The upper glume is longer than the flower.—Hierochloa.
9. Chlorideæ. The spikelets are arranged in the form of a spike in two rows on one side of an often flatly-compressed axis; they are mostly 1-flowered.—Chloris; Ctenium; Cynodon; Eleusine; Microchloa.
10. Paniceæ. The spikelets are borne in panicles or spikes, which may be arranged like fingers or in a raceme. There is a centrally-placed ☿-flower; below it is sometimes a ♂-flower.—Panicum; Paspalum; Oplismenus; Setaria has an almost cylindrical spike-like panicle with several barren branchlets, which project as stiff, rough bristles.—Cenchrus; Pennisetum.
11. Hordeæ. Spikes compound; spikelets sessile in the notches of a toothed axis.
A. Spikelets solitary.—Triticum (Wheat, Fig. [287]) has in each tooth of the main axis, a several-flowered spikelet which turns its flat side towards the central axis. The cultivated species (true Wheat) are 1-2-annual, the wild ones (T. repens, Couch, also as an independent genus, Agropyrum) are perennial, with creeping rhizome and lanceolate glumes.—Lolium (Rye-grass) has in each tooth of the main axis a many-flowered, compressed spikelet, which is placed edgewise towards it and (with the exception of L. perenne) has only one outwardly-turned glume (L. temulentum has a rudiment of the inwardly-turned lower glume); the terminal spikelet has two glumes.—Secale (Rye). A two-flowered spikelet in each tooth; small, lanceolate, acuminate glumes. Nardus and Lepturus have very narrow spikes, the former with unilateral spikelets.
B. In each notch of the axis 2 or more spikelets are placed close together.—Hordeum (Barley). In each tooth three 1-flowered spikelets. H. hexastichum (6-rowed Barley), has 6 rows of fruits, since all the spikelets are fertile, and H. distichum (2-rowed Barley) 2 rows, since the lateral spikelets are (♂, and barren (p. [292]).—Elymus has 2–6 many-flowered spikelets in each joint of the main axis. Ægilops has awns upon the glumes.