. The elements of botany for beginners and for schools. Botany. SECTION 10.] PISTILS. 109 tiguous margius of two pistil-leaves grown together. There is every grada- tion between tLis and the three-celled ovary with the placenta; in the axis, even in the same genus, sometimes even in different stages in the pistil (Fig. 335, 336). § 2. GYMNOSPERMOUS GYNCECIUM. 313. The ordinary pistil lias a closed ovary, and accordingly tlie pollen can act upon tlie contained ovules only indirectly, llirougli tlie stigma. This is expressed in a term of Greek derivation, viz.: — Aiigiospermous, meaning t
. The elements of botany for beginners and for schools. Botany. SECTION 10.] PISTILS. 109 tiguous margius of two pistil-leaves grown together. There is every grada- tion between tLis and the three-celled ovary with the placenta; in the axis, even in the same genus, sometimes even in different stages in the pistil (Fig. 335, 336). § 2. GYMNOSPERMOUS GYNCECIUM. 313. The ordinary pistil lias a closed ovary, and accordingly tlie pollen can act upon tlie contained ovules only indirectly, llirougli tlie stigma. This is expressed in a term of Greek derivation, viz.: — Aiigiospermous, meaning that the seeds are borne in a sac or closed vessel. The counterpart term is Gymmspermous, meaning naked-seeded. This kind of pistil, or gyiioe- cium, the simplest of all, yet the most peculiar, characterizes the Pine family and its relatives. 314. While the ordinary simple pistil is conceived by the botanist to be a leaf rolled together into a closed pod (306), those of the Pine, Larch (Fig. 337), Cedar, and Arbor-Vitse (Fig. 338, 339) are open leaves, in the form of scales, each bearing two or more ovules on the inner face, next the base. At the time of blossoming, these pistil-leaves of the young cone diverge, and the pollen, so abundantly shed from the stam- iuate blossoms, falls directly upon the exposed ovules. Afterward the scales close over each other until the seeds are ripe. Then ihey sepa- rate that the seeds may be shed. As the pollen acts directly on the ovules, such pistil (or organ acting as pistil) has no stigma. 315. In the Yew, and in Torreya and Gingko, the gynoeeium is reduced to extremest simplicity, that is, to a naked ovule, without any visible carpel. 316. In Cycas the large naked ovules are borne on the margins or lobes of an obviims open leaf plants have other peculiarities, also distinguishing Angiosfermous Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration
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