MR. G. BENTHAM ON GRAMINER. 97 
straight awns, one on each side of the dorsal twisted one, and in 
the grain glabrous or slightly pubescent at the apex without the 
longitudinal furrow of Avena. The inflorescence is also usually 
more dense than in that genus, with smaller, often shining spike- 
lets. A few African or South-American species, however, such 
as T. hirtum, Nees, and T. antarcticum, Nees (which includes 
Bromus antarcticus, Hook. f., and Bromus bicuspis, Nees), closely 
connect the two genera: the flowering glume is more rigid and 
less keeled than in the true Triseta, and the ovary is pubescent 
at the top but the grain has not the furrow of Avena. Tricheta, 
Beauv., is the Trisetum ovatum, Pers., a species allied to T. sub- 
spicatum; but the spikelike panicle is more dense and ovoid, or 
almost globular. Acrospelion or Acropselion, Bess., is Trisetum 
distichophyllum, Beauv., not the Ventenata, Link, to which it is 
referred in Lindley’s ‘ Vegetable Kingdom.’ Rostraria, Trin., 
was made up of Trisetum neglectum, Roem. et Schult., and Keleria 
phleoides, Pers. 
8. VENTENATA, Koel, has two species, V. avenacea, Koel., and 
V. inacra, Balansa, from the Mediterranean region and Central 
Europe, differing slightly from Trisetum in the longer, more rigid, 
many-nerved glumes, and the absence of any dorsal awn on the 
lower flowering one. 
9. AvENA, Linn., as limited by recent authors, comprises about 
forty species, mostly from the temperate regions of the Old 
World, with a few from extratropical North and South America, 
and one or two of the annual ones cornfield weeds in other coun- 
tries. It is generally characterized by the flowering glumes 
rounded on the back and several-nerved, with a dorsal twisted or 
bent awn, and by the ripe grain furrowed in front and more or 
less adhering to the palea, but is divisible into two sections almost 
marked enough in habit as wellas character to be raised to the 
rank of genera. In 1. Crithe, Griseb., the species are all annual, 
usually tall, with a loose panicle of large pendulous spikelets, each 
containing no more than two fertile flowers, and often only a 
single one, and the lower empty glumes 7- or 9-nerved. This 
section includes the common Oat, which has lost its dorsal awn 
probably as a consequence of long cultivation; for the plant is 
unknown in a wild state, except here and there as an escape 
from cultivation. In 2. Avenastrum, Koch ( Helicotrichum, Bess.), 
the plant is perennial, the panicle usually narrow, with erect or 
rarely spreading spikelets with more than two perfect flowers, 
