104 CLASSIFICATION ACCORDING TO [CH. 
Melica uniflora, also a wood-grass, has the spikelets two- 
flowered, though the upper one may be a mere rudiment, and 
much fewer, on a flexuous nodding axis. The much rarer W/. nutans 
has two perfect flowers in the spikelet (see p. 105). 
(ii) Grasses of open situations, with numerous 
small pointed spikelets. Inner palea minute 
or absent. 
Agrostis. 
The genus most likely to give trouble here is Azra, which 
though normally with two flowers in the spikelet, occasionally has 
but one. As regards the common species of similar habit, &c., 
Aira has bristle-like leaves and Agrostis flat ones. 
Again, Agrostis alba has no protruding awn, as in the spikelets 
of Atra. For Aira cespitosa and other details, see p. 117. 
* Awnless, or at most a short bristle not 
equalling the palea. Leaves flat and 
short. 
A. alba, L. 
An exceedingly variable plant. The variety A. stolonifera has a 
less spreading panicle, and broader leaves with a long serrated 
and pointed ligule: the variety A. vulgaris has a spreading loose 
panicle, narrower leaves, and a short truncated ligule. There is, 
however, much difficulty in distinguishing the intermediate forms 
on mountain-pastures, &c. 
** Distinctly awned. Leaves narrower, the 
lower ones inrolled and almost setaceous. 
A. canina, L. 
The rarer A. setacea, Curt. with subulate leaves and A. Spica- 
venti, L. with long awns also come here. 
The lax spreading type of panicle characteristic of Aira and 
Agrostis, &c., described above, occurs in species of Avena, Bromus, 
Briza, Poa and Catabrosa, but the basal silky hairs and twisted 
awns (Avena), long sub-terminal bristle-awns (Bromus), habit 
