. Botany all the year round; a practical text-book for schools. Botany. MONOCOTYLEDONS AND POLYCOTYLEDONS 89. 202 203 202, 203. — Pitch pine seeds (Gray) ; 201, scale, or open carpel, with one seed in place; 203, winged seed, removed. like a samara of the maple, but it differs from all forms of the achene in being' a true seed and not a fruit. Notice that the pine has no closed seed vessel, or ovary, like the other specimens we have been considering, but bears its seed naked in the axil of the cone scales, which may be considered open carpels. Hence, plants of this kind are called Gyviiiosperm
. Botany all the year round; a practical text-book for schools. Botany. MONOCOTYLEDONS AND POLYCOTYLEDONS 89. 202 203 202, 203. — Pitch pine seeds (Gray) ; 201, scale, or open carpel, with one seed in place; 203, winged seed, removed. like a samara of the maple, but it differs from all forms of the achene in being' a true seed and not a fruit. Notice that the pine has no closed seed vessel, or ovary, like the other specimens we have been considering, but bears its seed naked in the axil of the cone scales, which may be considered open carpels. Hence, plants of this kind are called Gyviiiosperms, a word that means "naked ; Look at the bottom, or little end of the seed, with your lens, for a small opening like a pin hole. Make an en- larged drawing of the seed as it appears under the lens, labeling this hole micropyle, a Greek word meaning " a little gate," because it is the entrance to the interior of the seed. 'Remove the coat from a seed that has been soaked for twenty-four hours, and examine it with a lens. Pick out the embryo from the endosperm. Does the endosperm resemble that of the corn arfd wheat t Test it with iodine for starch. How does the embryo differ from those already examined.' How many cotyledons are there ? Plants having more than two seed leaves are said to be polycotyledonous, a word meaning "having many cotyle- ; This structure is characteristic of the pines, firs, hemlocks, and some other plants, mostly belonging to the Gymnosperms, or naked-seeded class. 204. — Section of pine seed, showing the poly- cotyledonous ennb(-yo (Gray). PRACTICAL QUESTIONS 1. What gives to Indian corn its value as food? To oats ; wheat; barley; rye; rice? (118, 119.) 2. Which of these grains have the larger proportion of starch or other endosperm to the embryo? 3. Do the husks or seed coats contain any nourishment?. Please note that these images are extracted from scanned page images that may have been digitally enhanced fo
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