Palea with 5-7 scaberulous ribs, but not hairy, flat above, incurved below, so that the inner palea is clearly visible. About 10-14 mm. long and narrowing somewhat suddenly into the smooth stiff awn, shorter than itself. Indications of a tooth at each side of the base of the awn. Caryopsis somewhat flattened, thin and long, barge-shaped, 8-10 × 1·5-2 mm., pointed at both ends, brown, hairy at the tip with the remains of the stigma. “Seed" often purplish. Rachilla long and slender.
Must be carefully distinguished from Brachypodium, which has the palea less inrolled and a stouter rachilla.
Bromus giganteus has a shorter and flatter “seed" and longer awn.
Bromus asper, Murr. (Fig. [71]).
Palea often reddish, 5-7 ribbed and usually roughly hairy, mid-rib scaberulous, about 15 mm. long, linear-lanceolate (barge-shaped), the tip more distinctly two-toothed and tapering more gradually into the smooth awn, about its own length. Rachilla distinct. Otherwise resembling B. erectus.
B. giganteus has a shorter “seed" and longer awn.
ΔΔ Palea scarcely hairy: awn up to twice its length.
Bromus sterilis.
B. giganteus.
| Bromus sterilis. B. giganteus. |
Bromus sterilis, L. (Fig. [50]).
Palea nearly smooth, somewhat inrolled, terete-lanceolate-acuminate, tough, red-brown, 12-15 mm. long, seven-ribbed, with a long serrulate awn (20-30 mm. or more) practically terminal. Ribs serrate. Caryopsis 9-10 mm. long, flattened, thin. Rachilla distinct, smooth, much wrapped in, widens upwards and is somewhat flattened.
The very slender and long “seed" and caryopsis distinguish this from all but B. erectus, which has a shorter awn. Perhaps the awn is truly terminal: if so it should go with Festuca Myurus, &c. (see p. [171]). The length varies greatly.