Alternative names: Not Applicable

Description:
Herbs "grasses" with alternate leaves embracing the stem with long sheaths which are slit at maturity on the side opposite to the blade and are usually convolute (i.e. 1 margin rolled over the other); sheath ending at the base of the blade in a tongue-like membrane (ligule), sometimes very short or reduced to hairs; stems usually hollow between the nodes; when the blades are narrow the margins usually involute; most of the stem (or sometimes all of it) usually concealed by the leaf sheaths (when they are termed intravaginal innovations); the nodes are the swollen bases of the sheaths.

Flowers small, bisexual, rarely unisexual, naked in the axil of a concave bract (the lemma), opposite to and enclosed in which is another usually 2-nerved bract (the palea); the palea envelopes the flower, which consists of a 1-celled carpel with I ovule and 2 styles with feathery stigmas and usually 3 stamens with versatile anthers; (the term "flower" is generally understood to include the lemma and palea); at the base of the ovary are 2 (rarely 1, 3 or 0) minute delicate scales (the lodicules) usually regarded as the perianth; below the lemma and palea, and enclosing them more or less, are 2 empty bracts (the glumes); all these together form a 1-flowered spikelet, but there may be several flowers arranged alternately on opposite sides of a common axis (the rhachilla)--so that the upper flowers often appear to be stalked-with the glumes at the base, the whole forming a several-flowered spikelet; spikelets arranged in a spike, raceme or panicle.

The fruit (grain or caryopsis) consists of the single albuminous seed and the thin pericarp, which are usually inseparable; at the base of the fruit and on its anterior or outer side (i.e. that which faces the lemma) is a small protuberance showing the position of the embryo; on the posterior or inner side (that facing the palea) is either a punctiform or linear mark (the hilum), which indicates the spot where the ovule was attached to the wall of the ovary; the hilum often lies in a furrow.

Distribution:  More than 600 genera and 10,000 species, cosmopolitan, more than 200 genera and 1,000 species in Australia.

Biology: No text

Taxonomic notes: Genera are grouped into tribes to bring related genera together. The allocation of genera to tribes is, however, controversial and many of the placings used here may prove to be unsatisfactory.

Key to Genera:

6. Glumes 5-7-nerved, longer than the lemmas	SCHISMUS 15.
6. Glumes 1-3-nerved, shorter than the lemmas
7. Lemma obtuse or truncate, minutely denticulate	PUCCINELLIA 37.
7. Lemma notched, often with a short mucro in the notch
8. Spikelets 2-flowered	MOLINERIELLA 50.
8. Spikelets 3-10-flowered
9. Lemmas rounded or flat on their back
10. Perennials; lemmas mucronate	DIPLACHNE 70.
10. Annuals; lemmas without a mucro	DESMAZERIA 29.
9. Lemmas keeled by a prominent nerve on their back
11. Lemma thin, hairy towards the base	POA 36.
11. Lemma cartilaginous, glabrous	SCLEROCHLOA 38.
4. Lemma entire
12. Spikelet 2-flowered
13. Lemma thick and hard	ISACHNE 18.
13. Lemma thin
14. Glumes 1-3-nerved	POA 36.
14. Glumes 7-15-nerved
15. Spikelets drooping and quivering	BRIZA 26.
15. Spikelets erect	ERIACHNE 11.
12. Spikelet 3-several-flowered
16. Lemmas rounded on the back
17. Spikelets drooping and quivering	BRIZA 26.
17. Spikelets erect
18. Lemma acute	FESTUCA 31.
18. Lemma obtuse
19. Lemmas 1.5-3 mm long
20. Panicle 1-sided; annuals	DESMAZERIA 29.
20. Panicle symmetrical; mostly perennials	PUCCINELLIA 37.
19. Lemmas 6-10 mm long	GLYCERIA 32.
16. Lemmas keeled
21. Spikelets sessile, in scattered spikes	LEPTOCHLOA 74.
21. Spikelets in a loose or contracted panicle
22. Spikelets in compact clusters	DACTYLIS 28.
22. Spikelets not clustered
23. Ligule membranous
24. Lemma hard, glabrous, 5-nerved; panicle spike- like	SCLEROCHLOA 38.
24. Lemma thin; panicle usually loose
25. Lemma rounded on the back below	FESTUCA 31.
25. Lemma keeled on the back to the base
26. Lemma woolly near the base, 5-9-nerved	POA 36.
26. Lemma glabrous, 3-nerved	SPHENOPUS 39.
23. Ligule of hairs or a hair-fringed membrane
27. Glumes 1-nerved; lemmas 3-nerved	ERAGROSTIS 73.
27. Glumes 4-7-nerved; lemmas 7-9-nerved	PLAGIOCHLOA 35.

Author: Prepared by J.P. Jessop except where indicated