264 A TEXT-BOOK OF BOTANY 
and the grain is the characteristic seed-like fruit. The 
flowers occur in small close clusters, and associated with 
them are peculiar bracts characteristic of the family 
(Fig. 260). For example, these bracts form the so-called 
chaff of wheat and other 
cereals, where they persist 
and more or less envelop 
the grain. These little 
clusters of bracteate flow- 
ers are arranged to form 
either a loose and spread- 
ing general cluster, as in 
red top and oats (Fig. 
262), or else a compact, 
spike-like cluster, as in 
timothy and wheat (Fig. 
261). 
When the uses of 
grasses are considered, it 
: becomes evident that this 
Fra. 260.—Oats: A, part of a flower-cluster, 18 by far the most impor- 
showing the bracts, in the axils of which tant family of plants to 
flowers appear; B, a single flower, with : : 
its enveloping bract, three stamens,and man. It 18 possible to 
Toles After Baizow, Suggest only some of the 
conspicuous formas. 
(1) Cergars.—This group includes those grasses that 
are cultivated for their seed-like fruits or grains, and they 
represent the chief interest of agriculture. What cereals 
mean as a food-supply for the world is too well known to 
need explanation. The most extensively cultivated cereals 
are as follows: 
Wheat.—This is certainly the best known and most 
valuable of all cereals. The original home of wheat is 
unknown, for it has been cultivated from the very earliest 
times. It is a crop peculiarly adapted to regions of cold 
