1, single spikelet; 2, single flower with awned plume and palea; 3, pistil; 4, grain.
Each spikelet contains a solitary flower with two outer small barren glumes, above which is a large tough, compressed, often awned, flowering glume, which partly encloses the somewhat similar pale.
- Spikelet of Anthoxanthum (enlarged) without the two lower barren glumes, showing the two upper awned barren glumes (g) and the flower.
The species of Heteropogon, a cosmopolitan genus in the warmer parts of the world, have strongly awned spikelets.
Aristida and Stipa are large and widely distributed genera, occurring especially on open plains and steppes; the conspicuously awned persistent flowering glume forms an efficient means of dispersing the grain.