And rare grasses like Polypogon, Gastridium, &c.
Inflorescence, a loose plume-like or branched panicle.
Avena.
Bromus.
Arrhenatherum.
Catabrosa.
Aira (except A. præcox and
A. canescens).
Arundo.
Digraphis.Milium.
Agrostis.
Melica.
Holcus.
Poa (most of the species).
Glyceria.
Briza.
Festuca (except F. Myurus).
|
Avena. Bromus. Arrhenatherum. Catabrosa. Aira (except A. præcox and A. canescens). Arundo. Digraphis. | Milium. Agrostis. Melica. Holcus. Poa (most of the species). Glyceria. Briza. Festuca (except F. Myurus). |
And the rare Hierochloe.
The Glumes are always present in our grasses, and rudimentary only in the rare grass Leersia; but Lolium and Nardus have only one glume to the spikelet, and Hierochloe, Digraphis and Anthoxanthum (Fig. [32]) have four or six. Our other grasses have two, but often unequal in size.
In shape they are usually boat-like, pointed or obtuse (Briza) and frequently with a distinct keel (Anthoxanthum, Digraphis, Phleum, &c.) or with ridges, green lines (veins) and other characteristic markings (e.g. Digraphis). The tip may be extended into a stiff long point or awn (Agropyrum, Phleum, Nardus) and the keel, ribs, and awn may have hairs or serrulæ on them. The rule is, however, that the glumes are not awned. In texture the glumes may be herbaceous and green-brown or purple (e.g. Melica) or membranous or stiff, or scarious (i.e. browned, as if scorched) at the edges. In Hordeum some of the glumes are so narrow and pointed as to resemble stiff awns. In Catabrosa the glumes are truncate, as if bitten off at the top.
The Paleæ are also often more or less boat-shaped, or flat ovate or oblong scales, usually more delicate than the glumes and frequently pointed, or (especially the outer pale) awned at the tip: in some cases, however, the awn springs from the middle or base of the back of the pale, and the latter may be bifid at its apex. The pale has usually a distinct middle nerve. The inner pale is commonly the smaller and more delicate of the two, and is sometimes difficult to see.
Conspicuously awned Grasses.
Avena.
Arrhenatherum (Fig. [33]).
Hordeum.
Bromus.Agropyrum caninum.
Lolium temulentum.
Brachypodium sylvaticum.
Festuca Myurus.And a few rare grasses like Panicum, Polypogon, Lagurus.
Grasses with no true awns.
Kœleria.
Milium.
Digraphis.
Elymus.
Festuca (except F. Myurus
and F. uniglumis).
Briza.Poa.
Glyceria.
Catabrosa.
Molinia.
Melica.
Psamma.
Agrostis alba.And a few rare forms like Leersia, Hierochloe, &c.
Grasses with inconspicuous awns, or mere points, to some of the Glumes or Pales.
Arundo.
Phleum.
Alopecurus.
Holcus.
Nardus.
Agropyrum repens.Lolium perenne.
Brachypodium pinnatum.
Dactylis.
Cynosurus.
Sesleria.
|
Avena. Arrhenatherum (Fig. [33]). Hordeum. Bromus. | Agropyrum caninum. Lolium temulentum. Brachypodium sylvaticum. Festuca Myurus. |
|
Kœleria. Milium. Digraphis. Elymus. Festuca (except F. Myurus and F. uniglumis). Briza. | Poa. Glyceria. Catabrosa. Molinia. Melica. Psamma. Agrostis alba. |