CHAPTER VII 
A FEW IMPORTANT PLANT FAMILIES 
The Grass 
Family. — This is perhaps our most important 
family of plants as it furnishes us the cereal grains and much 
other food for man and beast. The plants have stems that 
SECTION OF 
Corn STALK 
a. Solid joints. 
b. Partof blade 
of leaf. 
c. Enveloping 
sheath. 
of the ovary 
are solid at the joints and usually hollow be- 
tween; in Indian corn and a few other species 
the stem is not hollow, but pithy. The leaves 
are alternate and parallel veined ; the basal part 
envelops the stem, forming a sheath that is open 
on the side opposite the blade. 
A good example for studying the structure of 
the flower is the head of wheat. This ‘‘head” 
is what botanists calla spike, and consists of two 
_| rows of spikelets attached alternately on opposite 
| sides of a jointed stem. Each of these spikelets 
~| contains several flowers, but they are quite in- 
conspicuous, as the showy calyx and corolla are 
absent and we have only the stamens and pistil, 
and these are inclosed within scales or chaff. 
There are three stamens, and when the wheat is 
in full bloom we may see the anthers dangling 
by their slender filaments. The pistil consists 
or kernel and two styles and feathery stigmas. 
In barley and rye the flower clusters have the form of a 
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