=Gymnospermous Fruits.=--In pine, spruces, and their kin, there is no
fruit in the sense in which the word is used in the preceding pages,
because _there is no ovary_. The ovules are naked or uncovered, in the
axils of the scales of the young cone, and they have neither style nor
stigma. The pollen falls directly on the mouth of the ovule. The ovule
ripens into a seed, which is usually winged. Because the ovule is not
borne in a sac or ovary, these plants are called =gymnosperms= (Greek
for “naked seeds”). All the true cone-bearing plants are of this class;
also certain other plants, as red cedar, juniper, yew. The plants are
monœcious or sometimes diœcious. The staminate flowers are mere naked
stamens borne beneath scales, in small yellow catkins which soon fall.
The pistillate flowers are naked ovules beneath scales on cones that
persist (Fig. 29). Gymnospermous seeds may have several cotyledons.
SUGGESTIONS.--=168.= Study the following fruits, or any five fruits
chosen by the teacher, and answer the questions for each: Apple,
peach, bean, tomato, pumpkin. What is its form? Locate the scar left
by the stem. By what kind of a stem was it attached? Is there any
remains of the blossom at the blossom end? Describe texture and color
of surface. Divide the fruit into the seed vessel and the surrounding
part. Has the fruit any pulp or flesh? Is it within or without the
seed vessel? Is the seed vessel simple or subdivided? What is the
number of seeds? Are the seeds free, attached to the wall of the
vessel, or to a support in the center? Are they arranged in any
order? What kind of wall has the seed vessel? What is the difference
between a peach stone and a peach seed? =169.= The nut fruits
are always available for study. Note the points suggested above.
Determine what the meat or edible part represents, whether cotyledons
or not. Figure 248 is suggestive. =170.= Mention all the fleshy
fruits you know, tell where they come from, and refer them to their
proper groups. =171.= What kinds of fruits can you buy in the market,
and to what groups or classes do they belong? Of which ones are the
seeds only, and not the pericarps, eaten? =172.= An ear of corn is
always available for study. What is it--a fruit or a collection of
fruits? How are the grains arranged on the cob? How many rows do you
count on each of several ears? Are all the rows on an ear equally
close together? Do you find an ear with an odd number of rows? How
do the parts of the husk overlap? Does the husk serve as protection
from rain? Can birds pick out the grains? How do insect enemies enter
the ear? How and when do weevils lay eggs on corn? =173.= _Study a
grain of corn._ Is it a seed? Describe the shape of a grain. Color.
Size. Does its surface show any projections or depressions? Is the
seed-coat thin or thick? Transparent or opaque? Locate the hilum.
Where is the silk scar? What is the silk? Sketch the grain from the
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