. Elementary botany . Botany. IS4 DICOTYLEDONS lobed and divided into four chambers, each containing one ovule; style attached between the bases of the four lobes of the ovary. Fruit a schizocarp of from one to four nutlets. Typp: WHITE DEAD NETTLE (Lamium album). Vegetative characters.—Perennial herb with a four-sided stem. Leaves opposite, exstipulate, with scalloped or saw-like margins. Inflorescence.—Each infioresence which stands in the axil of a leaf is a dichasium with a terminal flower and two lateral one - branched cymes (monochasia). Flower (fig. 191) median-zygomor- phic, $, cyclic,
. Elementary botany . Botany. IS4 DICOTYLEDONS lobed and divided into four chambers, each containing one ovule; style attached between the bases of the four lobes of the ovary. Fruit a schizocarp of from one to four nutlets. Typp: WHITE DEAD NETTLE (Lamium album). Vegetative characters.—Perennial herb with a four-sided stem. Leaves opposite, exstipulate, with scalloped or saw-like margins. Inflorescence.—Each infioresence which stands in the axil of a leaf is a dichasium with a terminal flower and two lateral one - branched cymes (monochasia). Flower (fig. 191) median-zygomor- phic, $, cyclic, hypogynous. Sepals (ex) five, combined. Petals {pp, Ip, ap) five, com- bined to form a two-lipped corolla. In order to under- stand that there are five petals represented in the corolla, it is necessary first to remember that the petals alternate with the sepals. It will then be seen that the three-lobed lower lip represents one anterior petal {ap) and two lateral petals {Ip) alternating with two anterior sepals. In like manner the upper lip of the corolla represents two pos- terior petals (//), one on each side of the median posterior sepal (see diagram fig. 192). The slight notch in the apex of the upper lip also denotes that the latter represents two closely joined petals. A ring of hairs {h) lines a zone of the corolla-tube. Stamens four, the two anterior stamens having longer filaments than the other pair, inserted on the corolla. In order to understand the androecium we must again remember that the stamens should alternate with the petals. There should, therefore, be a median posterior stamen, but no such stamen is present. We therefore con- clude that the median posterior stamen has been suppressed:. Fig. igi.—Vertical section of iiower of Dead 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
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1898
