. Botany for agricultural students. Plants. 26 FLOWERS of hair-like structures called pappus, as shown in Figure 24- In some, as the Dandelion illustrates, the pappus remains after the seed is mature, forming a parachute-like arrangement which assists in floating the seed about. In some of the Composites, the calyx consists of a few teeth, which in the Spanish Needles and Beggar's Tick, become spiny, and thcreb}^ assist in seed distribution by catching onto passing objects. Orchid Flowers. — It is among Orchid flowers, many of which are spectacular, that the most notable irregularities occur.
. Botany for agricultural students. Plants. 26 FLOWERS of hair-like structures called pappus, as shown in Figure 24- In some, as the Dandelion illustrates, the pappus remains after the seed is mature, forming a parachute-like arrangement which assists in floating the seed about. In some of the Composites, the calyx consists of a few teeth, which in the Spanish Needles and Beggar's Tick, become spiny, and thcreb}^ assist in seed distribution by catching onto passing objects. Orchid Flowers. — It is among Orchid flowers, many of which are spectacular, that the most notable irregularities occur. Besides the dis- tinguishing feature of having the stamens and pistil joined into one body, known as the column, Orchid flowers often have pronounced varia- tions in the shape and size of petals. In some, as in the Lady's-slipper, one of the petals is developed into a great sac or " slipper," while the others have no extraordinary features. These peculiarities in flower structure, which are apparently adjustments for insect pollination, sometimes so closely con- form to the shape and habit of cer- spadix which is enclosed in the tain insects that only one or a few large leaf-hke bract or spathc. kinds of insects can pollinate a flower. Reduced about one-half. g^^^ highly modified flowers contrast strikingly with the simple, inconspicuous flowers of such plants as the Jack-in-the-pulpit or Indian Turnip and Skunk Cabbage, in which a perianth is either lacking or inconspicuous and the flowers are crowded on a fleshy spike, known as a spadix, which is enclosed in or attended by a leaf, called spathe. The spathe, by becoming colored, often aids like a corolla in attracting insects. (Figs. 25 and 26.). Fig. 26. — The inconspicu- ous flowers of the Indian Turnip (Arisoema Iriphyllum). The flowers shown are pistil- late and are clustered at the base of the fleshy Arrangement of Flowers or Inflorescence The arrangement of flowers on the stem is one of the floral character
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectplants, bookyear1919
