. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. 352 SEEDS is present in sufficient quantity to render the kernels of some species of Pines of nutritive value. The method of germination of the seeds is practically the same as that of a Castor Oil, the seedlings (Fig. 195) possessing long hypocotjds (/;.) with epigeal cotyledons {coi.). During the development of the embrj'o the entire ovule enlarges considerably, and at the same time the integument hardens to form the seed-coat, or testa (s.). The greater part of the. Fig. 205.—Seeds and cones of various Con
. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. 352 SEEDS is present in sufficient quantity to render the kernels of some species of Pines of nutritive value. The method of germination of the seeds is practically the same as that of a Castor Oil, the seedlings (Fig. 195) possessing long hypocotjds (/;.) with epigeal cotyledons {coi.). During the development of the embrj'o the entire ovule enlarges considerably, and at the same time the integument hardens to form the seed-coat, or testa (s.). The greater part of the. Fig. 205.—Seeds and cones of various Conifers. A, longitudinal section of ripe seed of the Stone Pine {Pi)iiis pinca), sfiowing the testa (s), theperisperm (n, cf. p. 371), endosperm (c), and the embryo with radicle (c) and numerous cotyledons (Co) ; H, young female cone of Juniper [Juniperus) and C, ripe cone of same ; D, outer edge of ripe cone- scale of WcUingtonia (Sequoia) ; E, single cone-scale of Piints bearing the two seeds with wings (w) ; F, ripe cone-scales of Douglas Fir (Psciidotsiign). , bract scale ; , ovuliferous scale. (B, after Antoine.) latter comes to consist of very thick-walled tissue, foreshadowed as a dark zone in the integument of a young P/;;//s-ovule (Fig. 203, A, s.), and constituting the hard la\'er which is so conspicuous a feature in the seed of the Stone Pine (Pi 11 lis pinca). The micropyle appears on the testa as a minute opening, and it will be realised, from the foregoing description, that the tip of the radicle lies just beneath this. In Piinis and some of its allies, a thin membranous flake liecoivics detached from the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Fritsch, Felix Eugene, 1879-; Salisbury, E. J. (Edward James), Sir, b. 1886. London, G. Bell and sons ltd.
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpl, booksubjectplants
