Poaceae
Spikelets bisexual (rarely unisexual, and if so, the spikelets similar and in the same inflorescence)
Spikelets not as in Group 13
Inflorescence a solitary spike or raceme (Fig. 47)
Spikelets sunken in the rhachis and scarcely protruding beyond the contour of the rhachis until they open
Inflorescence rhachis thickened. Spikelets closely appressed and sometimes embedded in the rhachis (Fig. 47 h)
Inflorescence rhachis not markedly thickened, spikelets not embedded in the rhachis