Caryopsis about 1·1 mm. long, oblong, yellow, corn-shaped, furrowed, shining through.
A. vulgaris, L., is a variety with slightly smaller fruits, no awn, and usually three nerves to the palea, but they cannot be distinguished with certainty by the "seed." Rachilla obsolete.
The colour of the glumes may vary considerably and is sometimes yellow.
The absence of awn, rachilla, and basal hairs distinguishes Agrostis from Aira.
ΔΔ Palea membranous, ribbed, tips scarious.
Glyceria aquatica.
G. fluitans.
Glyceria aquatica, Sm.
Palea strongly 5-7 ribbed, obtuse and scarious, about 4 mm. long. Green with a purple cast. Caryopsis dark-brown, about 2 mm. long.
Inner palea punctate. Rachilla slender and cylindrical.
Glyceria fluitans, Br., is very similar, but longer (6 mm.) and more slender; the palea scabrid with truncate or ragged tips, and the inner palea not punctate. Yellow. (Fig. [46].)
Glyceria aquatica and G. fluitans are sweet grasses of value in water-meadows only. The “seed" is not often met with.
Not only with the Poas, but also with Catabrosa are there difficulties in determination. Molinia and Kœleria also present difficulties with Glyceria: the former has fewer and feebler nerves. Digraphis and Arundo are easily distinguished by the basal hairs.
≡ ≡ Palea acute and somewhat compressed and keeled, and with hairs on the ribs. Tips nerved.
Poa annua.
P. maritima.
P. distans.
P. rigida.
P. loliacea.
P. bulbosa.
P. alpina.Their “seeds" are all small, about 2-3·5 mm. only, and angular, brown, and present many difficulties (see note, p. [141]).
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Poa annua. P. maritima. P. distans. P. rigida. P. loliacea. P. bulbosa. P. alpina. |