. The classification of flowering plants. Plants. COMPOSITAE 603 278, A), they are woven into a delicate weV) by transverse con- nections. Tn other cases, as daiUardia, the pa])pus consists of a whorl of broad light scales. Wing-like developments sometimes occur on the sides of the fruits, as in Verhesina (two-winged) or Tripteris (three-winged) or the bract subtending the female flower forms an enveloping wing, or, as in the female flowers of Zinnia, the Hat ligular corolla persists in the fruit as a broad wing. The fruit of Diotis maritima (Cotton-weed), which is widely dis- tributed on the
. The classification of flowering plants. Plants. COMPOSITAE 603 278, A), they are woven into a delicate weV) by transverse con- nections. Tn other cases, as daiUardia, the pa])pus consists of a whorl of broad light scales. Wing-like developments sometimes occur on the sides of the fruits, as in Verhesina (two-winged) or Tripteris (three-winged) or the bract subtending the female flower forms an enveloping wing, or, as in the female flowers of Zinnia, the Hat ligular corolla persists in the fruit as a broad wing. The fruit of Diotis maritima (Cotton-weed), which is widely dis- tributed on the shores of the Mediterranean and of the Atlantic from Britain (rare) to the Canaries, floats by means of a spongy development of the persistent corolla-tvibe, which grows down- wards and surrounds the greater part of the Fig. 278. Fruit of A, Tragopogon major, slightly reduced; B, Bidens cernua, x o. In other cases spine- or hook-developments ensure distribution by means of the fur of mammals or the feathers of birds. Such are the few stiff manj^-barbed pappus-bristles of Bidens (fig. 278) and allied genera, the hooked spines covering the outside of the involucral bracts of Xanthium (fig. 277, E) or the familiar stiff spreading hooked tips of the bracts of Burdock, which cause the whole head to be carried off. In Tragoceros, a small Mexican genus allied to Zinnia, the corolla of the female flower persists in the fruit and becomes bent back, forming a stiff simple or double hook. In Siegesbeckia orientalis, a species widely distributed in the w armer regions of the whole world, the involucral and smaller floral bracts bear sticky glandular hairs to which indi\4dual fruits adhere and are thus transported. A very exceptional case is afforded by the small tropical American genus Milleria, where a large bract encloses the small head, containing only one female. Please note that these images are extracted from scanned page images that may have been digitally enhanced for reada
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectplants, bookyear1904
