. Botany for young people and common schools. How plants grow, a simple introduction to structural botany. With a popular flora, or an arrangement and description of common plants, both wild and cultivated. Botany. 74 HOW PLANTS ARE Fig. 189, pistil of Common St. John's-wort, plainly composed of three simple ones, with their ovaries completely united, while their slender styles are separate. Fig. 190, same of Shrubby St. John's-wort, like the last, but with the three styles also grown together into one, the little stigmas only sepa- rate ; but as it gets older this style generally
. Botany for young people and common schools. How plants grow, a simple introduction to structural botany. With a popular flora, or an arrangement and description of common plants, both wild and cultivated. Botany. 74 HOW PLANTS ARE Fig. 189, pistil of Common St. John's-wort, plainly composed of three simple ones, with their ovaries completely united, while their slender styles are separate. Fig. 190, same of Shrubby St. John's-wort, like the last, but with the three styles also grown together into one, the little stigmas only sepa- rate ; but as it gets older this style generally splits down into three, and when the pod is ripe it aLo splits into three, plainly showing that this compound pistil consists of three united into one. On turning now to Fig. 8 and Fig. 10 to 12 on the same page, it Avill be seen that the pistil in Morning-Glory and in Lily Compound Pistils of two anil three ctiu. Is a compouud ouc, uiadc of three united even to their stigmas. This is shown externally, by the stigma being some- what threc-lobed in both. And it becomes perfectly evident on cutting the ovary in two, bringing to vicAV the three cells (Fig. 12, as in Fig. 189, 190), each an- swering to one simple ovary. 216. So compound ovaries generally have as many cells as there are simple pistils or pistil-leaves in their composition ; and have the placentas (199) bearing the seeds all joined in the centre: that is, the placentas or compound placenta in the axis. But sometimes the partitions or divisions between the cells vanish, as in Pinks : then the compound pistil is only one-celled. And sometimes there never were any partitions; but the pistil was formed of two, three, or more open pistil-leaves grown together from the first by their edges, just as petals join to make a monopetalous corolla. Then the ovules or seeds, or the placentas that bear them, are parietal^ that is, are borne on the parietes or wall of the ovary. Fig. 191 is the lower part of a compound ovary, with
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