. The origin of floral structures : through insect and other agencies. Plants; Flowers; Flowers. THE PRINCIPLE OF AEEANGEMENT. 43 tt. fft. the flower, througli which nourishment is withdrawn at certain places to produce hypertrophy elsewhere. Thus the sepaline cord, instead of bearing an anther in Primula, bifur- cates at the angle, and each branch proceeds up the margin of a lobe of the corolla, and aids in nourishing the latter. As a converse instance of the sepaline cord undertaking a considerable amount of work, may be mentioned Gampanula â medium. In this plant the 5-lobed fibro-vascular
. The origin of floral structures : through insect and other agencies. Plants; Flowers; Flowers. THE PRINCIPLE OF AEEANGEMENT. 43 tt. fft. the flower, througli which nourishment is withdrawn at certain places to produce hypertrophy elsewhere. Thus the sepaline cord, instead of bearing an anther in Primula, bifur- cates at the angle, and each branch proceeds up the margin of a lobe of the corolla, and aids in nourishing the latter. As a converse instance of the sepaline cord undertaking a considerable amount of work, may be mentioned Gampanula â medium. In this plant the 5-lobed fibro-vascular cylinder of the pedicel sends ofE five cords intended for the calyx (Fig. 8, sep.) ; but, before reaching the base of the superior sepal, it sends ofB an inner- most and lowest cord to become the dorsal one of the carpel (d. car.), which, in this flower, is thus super- posed to a sepal. It also sends off two, right and left, one for each petal alternating with it (pet.) ; so that each petal receives two cords, one from each adjacent sepal,âa -^ most unnsual condition of things, O .,âvOZT^^, â, for petals have almost invariably /^ II \ their own cords issuing from the ^x n_7 ^ pedicel. Lastly, the same sepaline Fie- SâVcrtical and transverae aec ^ . tions of the wall of the inferior cord provides that of the stamen ovary of campanula medium -,^ ji-i Til- (*"*"â ^^^ Tieghem). (St.) superposed to it. In this flower, therefore, we can understand why there is no petal- ine whorl of stamens; simply because the corolla does not possess its own proper fibro-vascular cords to give rise to them. On the other hand, in the Malvacece after the axis has supplied cords for the sepals, others furnish those of the corolla; these latter, however, by radial division form two. ^ 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 t
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Keywords: ., bookcentury1800, bookdecad, booksubjectflowers, booksubjectplants
