p.3

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EricRoscoe at Nov 19, 2022 07:50 PM

p.3

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Grasses are propagated by extending their roots, or rather underground stems called rhizomas or by seed. Those species that produce an abundance of seeds seldom increase very rapidly by their roots, while those most readily by their roots are less bountiful in the production of seed. Thus nature secures the presentation of each species, by one or other of these methods.

The minute pollen grains elaborated in the anthers are supposed to contain the true propagating cells. [each] These grains must find their way to the stigma at the time when this organ is in the proper state of growth to receive it; and its function here is essential to the [growth] perfection of the seed. The sac contained in the grain of pollen soon ruptures its coatings and penetrating through the openings in the stigma is elongated in a most wonderful manner until its extremity reaches the [crossed out] cavity at its base. The extremity of this pollen-tube here expanded and by the development of new cells forms the embryo, or little plant securely enveloped within the integuments of the seed.

The durability of seed is also one of the remarkable provisions for the preservation of plants. Had the wheat crop been entirely destroyed throughout the world, so that no seed was produced for a whole year, this invaluable grain would have been restored to us from seeds preserved for more than three thousand years in the foods of an Egyptian mummy. That seeds may also be buried in the ground and remain for a number of years until some favorable conditions cause them to germinate is also quite certain;

p.3

3

Grasses are propagated by extending their roots, or rather underground stems called rhizomas or by seed. Those species that produce an abundance of seeds seldom increase very rapidly by their roots, while those most readily by their roots are less bountiful in the production of seed. Thus nature secures the presentation of each species, by one or other of these methods.

The minute pollen grains elaborated in the anthers are supposed to contain the true propagating cells. [each] These grains must find their way to the stigma at the time when this organ is in the proper state of growth to receive it; and its function here is essential to the [growth] perfection of the seed. The sac contained in the grain of pollen soon ruptures its coatings and penetrating through the openings in the stigma is elongated in a most wonderful manner until its extremity reaches the [crossed out] cavity at its base. The extremity of this pollen-tube here expanded and by the development of new cells forms the embryo, or little plant securely enveloped within the integuments of the seed.

The durability of seed is also one of the remarkable provisions for the preservation of plants. Had the wheat crop been entirely destroyed throughout the world, so that no seed was produced for a whole year, this invaluable grain would have been restored to us from seeds preserved for more than three thousand years in the foods of an Egyptian mummy. That seeds may also be buried in the ground and remain for a number of years until some favorable conditions cause them to germinate is also quite certain;