Introduction to structural and systematic botany, and vegetable physiology, : being a 5th and revedof the Botanical text-book, illustrated with over thirteen hundred woodcuts . ne cycle to the next; — which is rather describingthe anomaly in other words than explaining it. 443. Whether we regard the floral circles as decussating verticils,or as cycles of alternate leaves in some way altered as to their suc-cession, we cannot fail to discern an end attained by such arrange-ment, namely, a disposition of parts which secures the greatest econ-omy of space on an abbreviated axis, and the greatest
Introduction to structural and systematic botany, and vegetable physiology, : being a 5th and revedof the Botanical text-book, illustrated with over thirteen hundred woodcuts . ne cycle to the next; — which is rather describingthe anomaly in other words than explaining it. 443. Whether we regard the floral circles as decussating verticils,or as cycles of alternate leaves in some way altered as to their suc-cession, we cannot fail to discern an end attained by such arrange-ment, namely, a disposition of parts which secures the greatest econ-omy of space on an abbreviated axis, and the greatest freedom frommutual pressure. 444. Position of the Flower as respects the Axis and subtending Bract. All axillary flowers are situated between a leaf and the stem, or,which is the same thing, between a bract and the axis of inflores-cence. These two fixed points enable us to indicate the relativeposition of the parts of the floral circles with precision. That partof the flower which lies next the leaf or bract from whose axil itarises is said to be anterior, or inferior (lower) : that which is dia-metrically opposite or next the axis is posterior, or superior (upper).*. It is important to notice the relative position of parts in this re-spect. This is shown in a proper diagram by drawing a sectionof the bract in its true position under the section of the flower-bud, as in Fig. 358 : the position of the axis is necessarily dia-metrically opposite, and its section is sometimes indicated by a dotor small circle. In an axillary flower with the parts hi fours, one of * As if these were not terms enough, sometimes the organ, or side of theflower, which looks towards the bract, is likewise called exterior, and the organor side next the axis, interior; but these terms should be kept to designate therelative position of the members of the floral circles in aestivation (494). FIG. 356. Diagram of a Cruciferous flower (Erysimum); a, the axis of inflorescence. (Thebract is abortive in thi
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Keywords: ., bookauthorgra, bookcentury1800, bookdecade1860, booksubjectbotany
