. Elements of botany. Plants. 154 ELEMENTS OF BOTANY. at first like an ordinary leaf and finally becomes folded in. What really occurs is this : the flower-bud, as soon as it has developed far enough to show the first rudiments of the essential organs, contains them in the form of minute knobs. These are developed from the tissues of the plant in the same manner as are the knobs in a leaf-bud, which afterwards become leaves ; but as growth and development progress in the flower-bud, its contents soon show themselves to be sta- mens and pistils (if the flower is a perfect one). The united _ lea
. Elements of botany. Plants. 154 ELEMENTS OF BOTANY. at first like an ordinary leaf and finally becomes folded in. What really occurs is this : the flower-bud, as soon as it has developed far enough to show the first rudiments of the essential organs, contains them in the form of minute knobs. These are developed from the tissues of the plant in the same manner as are the knobs in a leaf-bud, which afterwards become leaves ; but as growth and development progress in the flower-bud, its contents soon show themselves to be sta- mens and pistils (if the flower is a perfect one). The united _ leaf margins near the tip would form the stigma, and the placenta would corre- spond to the same margins, rolled slightly inwards, ex- tending along the inside of the inflated leaf pouch. Place several such folded leaves upright about a com- mon center, and their cross- section would be much like that of B in Fig. 132. Evi- dence that carpels are really formed in this way may be gained from the study of such fruits as that of the monkshood (Fig. 171), in which the ripe carpels may be seen to unfold into a shape much more leaf-like than that which they had while the pistil was maturing. 189. The Anther and its Contents. — Some of the shapes of the anthers may be learned from Figs. 116, 129, 136,138 and 155.^ The shape of the anther and the way in which it opens depend largely upon the way in which the pollen is to be dis-. FiG. 138. — Modes of Discharging Pollen. I, by longitudinal slits in the anther-cells (pine); II, by uplifted valves (barberry); III, by a pore at the top of each anther- lobe (rhododendron). See Kerner and Oliver, vol. II, pp. 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 Bergen, Joseph Y. (Joseph Young), 1851-1917; Bergen, Joseph Y. (Joseph Young), 1851-1917. Bergen's Botany: k
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectplants, bookyear1896
