. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. 358 OVULES bent down against its stalk (fiiniclc, f.), so that the micropyle {ni.) is directed towards the placenta. The greater part of the funicle is in this case fused with the adjacent portion of the outer in- tegument, which is in consequence not easily distinguished on this side. The fused region, known as the raphe {r.), is traversed by the vascular bundle {) which enters the funicle from the placenta, and which extends as far as the base of the nucellus (a region known as the chalaza, Ch.).. Fig.
. An introduction to the structure and reproduction of plants. Plant anatomy; Plants. 358 OVULES bent down against its stalk (fiiniclc, f.), so that the micropyle {ni.) is directed towards the placenta. The greater part of the funicle is in this case fused with the adjacent portion of the outer in- tegument, which is in consequence not easily distinguished on this side. The fused region, known as the raphe {r.), is traversed by the vascular bundle {) which enters the funicle from the placenta, and which extends as far as the base of the nucellus (a region known as the chalaza, Ch.).. Fig. 207.—Ovules and stages in their development (after Le Maout and Decaisne). A, Young ovule, before the integuments appear, showing nucellus (Nit.) and dividing archesporium (ar.). B, Orthotropous ovule of Polygoniini. C, Anatropous ovule in longitudinal section, showing funicle (/.) and raphe (r.). D, I-IV (in the direction of the arrow), successive stages in the development of the anatropous ovule of Chelidonium. E, Successive stages (in the direction of the arrow) in the development of the campylotropous ovule of the Mallow [Malva). i., inner integument ; n., nucellus ; 0., outer integument. Erect or orthotropous ovules, in which the micropyle faces away from the placenta, and lies at the opposite end to the usualljr short funicle (Fig. 207, B), are much less frequent, but are found, for example, in the Knotweeds [Polygonum). Another rare type, the campylotropous ovule (Fig. 207, E), seen in many Caryophy]lacc;e, is bent in such a wa)' that the stalk appears to be attached midway between the chalaza and 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 Fritsch, Felix Eugene, 1879-; Salisbury, E. J. (Edward James), Sir, b. 1886. London, G. Bell and sons ltd.
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Keywords: ., bookcentury1900, bookdecade1920, booksubjectpl, booksubjectplants
