. Plants and their uses; an introduction to botany. Botany; Botany, Economic. THE ^'EC;ETATI^'E ORGANS COAIPARED 341 (Fig. 291). Tlie relation of the very narrow mouse-tail leaf to one of the marsh-marigold type may be understood by supposing the nerves to be reduced to a single rib. A leaf in which the framework consists of only one or two ribs, may be termed co-stated The simple leaf of the silky clematis may be likened to a less narrowed marsh-marigold leaf in which, however, the ribs are reduced to one midrib from which veins are given off on either side. Or, better, we may. Fig. 296.—Stan
. Plants and their uses; an introduction to botany. Botany; Botany, Economic. THE ^'EC;ETATI^'E ORGANS COAIPARED 341 (Fig. 291). Tlie relation of the very narrow mouse-tail leaf to one of the marsh-marigold type may be understood by supposing the nerves to be reduced to a single rib. A leaf in which the framework consists of only one or two ribs, may be termed co-stated The simple leaf of the silky clematis may be likened to a less narrowed marsh-marigold leaf in which, however, the ribs are reduced to one midrib from which veins are given off on either side. Or, better, we may. Fig. 296.—Staniinodes. A, Anemone Pulsatilla. B, Ranunculus acris, view from above. C, same, cut vertically; the shaded area (S) indicating the surface secreting nectar. D, Nigella dnmcscena, view from above. .E, same, cut vertically; secreting surfaces (vS) shown as before. All variously enlarged. (Redrawn from Prantl.) Fig. 297.—Ovary of an anemony, opened to show the two pairs of rudi- mentary ovules above the single normal one, enlarged. (Baillon.) view it as an elongated leaf in which the framework was at first divided palmatelj' into three branches, the middle one of which again divided similarly, and this method of branch- ing continued during the elongation of the blade. However we may view the nervation, such a leaf in which a single midrib, or direct continuation of the petiole, gives off several or many lateral branches, is distinguished as pinnately nerved. The leaves of the pasque-flower are described as 'pinnately compound or The leaflets of the Christmas rose are pinnately nerved, the leaf as a whole being palmate or pedate. ' '-tate < L. casta, a rib. - Pin'-nate < L. -pinna, a feather, because the veins arise from the midrib as do the barbs of a feather from its 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 pe
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbotany, bookyear1913
