68 BOTANY. 
(Phleum), Meadow-grass (Poa), Cock’s-foot-grass (Dactylis), Sweet- 
vernal-grass (Anthoranthum), Fescue (Festuca), Dog’s-tail-grass (Cyno- 
surus), &c. The grains of many other grasses are used for food. 
Zizania aquatica supplies a kind of rice, in the North-western States ; 
Setaria germanica yields German millet; Panicum miliaceum gives a 
kind of millet in India, and Andropogon sorghum is known as Durra, 
an Indian grain. Phalaris canariensis is the source of the common 
canary-seed. The cereal grains have been so extensively distributed by 
man, that all traces of their native country are lost. They seem to be in 
many instances examples of permanent varieties or races kept up by 
cultivation. Their grain, or caryopsis, contains a large amount of starch 
and gluten. Their grasses used for fodder in some parts of the world 
attain a large size, such as Anthistiria australis, the Kangaroo-grass 
of New Holland, Tripsacum dactyloides, the Gama-grass of Mexico, and 
Dactylis cespitosa, the Tussac-grass of the Falkland Islands. Some of 
these are five or six feet in height, and are, nevertheless, sufficiently 
delicate to be used as food for animals. The Tussac has been introduced 
into England, and thrives well in peaty soils within the influence of 
the sea-spray. It promises to be a valuable grass in the Hebrides of 
Scotland. 
Sugar is a valuable product obtained from many grasses. It has been 
produced in Italy from Sorghum saccharatum, Sweet Sorgho; in China, 
from Saccharum sinense ; in Brazil, from Gyneriwm saccharoides ; in the 
West Indies, from Saccharum violaceum ; and in many other parts of the 
world, from S. oficinarum. The two last are commonly known as sugar- 
cane, and they are generally considered as varieties of a single species, 
Saccharum officinarum, which is now widely spread over various parts of 
the world. Six or eight pounds of the saccharine juice of the plant furnish 
one pound of raw sugar. The recent discoveries of Melsens and others, 
however, promise a much greater yield than this. 
Tribe 1. Andropogonee. Spikelets bifloral: inferior flowers always incom- 
plete. Palez: more delicate than the glumes, most often transparent. 
This tribe is of great interest from containing the genus Saccharum, or 
sugar-cane, the principal species of which, S. officinale, is shown on 
pl. 50, fig. 8. Here the figures, a to c, represent the entire plant in various 
‘stages; d to g, pieces of the stalk; and h, the flowers; 1h, three spikelets 
with a single flower below. Species of Sorghum furnish broom corn (S- 
saccharatum), guinea corn (S. cernuum), and Indian millet (S. vulgare). 
Tribe 2. Rotbelliacee. Spikelets, uni- or bi-floral, rarely trifloral, lodged 
in an excavation of the axis or rachis, sometimes solitary, sometimes 
geminate; the one pedicillate, the other subsessile. One flower in all the 
bifloral spikelets (either superior or inferior) very often incomplete. 
Glumes one or two, occasionally none, most generally coriaceous. Paleze 
membranaceous, rarely bearded. Styles one or two, sometimes very short, or 
none.. Rachis more generally articulated. 
Tribe 3. Hordeacee. Spikelets, several- (rarely one-) flowered, sessile on 
opposite sides of a zig-zag, channelled and toothed, sometimes jointed 
68 
