. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. 870 THE DISPERSION OF SPECIES BY MEANS OF FRUITS AND SEEDS. phenomenon in question is not merely a matter of conjecture, but has come actually under observation. About 10 per cent of all Flowering Plants possess fruits or seeds which are dispersed by means of clawed or barbed processes. This mode of dissemination is very like that whereby sticky fruits attain the same object. The part of the plant which is provided with these structures hooks on to the hairs, bristles, or feathers of any bird or othe
. The natural history of plants, their forms, growth, reproduction, and distribution;. Botany. 870 THE DISPERSION OF SPECIES BY MEANS OF FRUITS AND SEEDS. phenomenon in question is not merely a matter of conjecture, but has come actually under observation. About 10 per cent of all Flowering Plants possess fruits or seeds which are dispersed by means of clawed or barbed processes. This mode of dissemination is very like that whereby sticky fruits attain the same object. The part of the plant which is provided with these structures hooks on to the hairs, bristles, or feathers of any bird or other animal that happens to come into contact with it. The conse- quence is that it is torn away and carried off by the animal. This act of depredation is of course not intentional on the part of the creature that performs it; on the contrary, such appendages-a^ a source of discomfort, and are got rid of as soon as. Fig. 476.âSticky fruits. 'â Salvia glutinom. 2 stallied adliesive glands on the fruiting calyx of the same; xeo. ^ Plwitibago Capemis. ^ Pisonia aculeata. s Stalked adhesive glands on the fruit of the same; x60. ^ Linnceaborealis. ? Fruit of the same; x5. possible. But in many cases this is not accomplished until a considerable distance has been traversed, and sometimes the troublesome objects remain for weeks in the creature's coat or mane. The organs of attachment are either hooked at the tip or beset with barbs (see figs. 477 ^ and 477 ^). In the latter case the barbs are borne on special rigid bristles or needles, and are either collected together at the top, as in a harpoon, or else are arranged in longitudinal rows as in a hackle for combing flax. Only in a few instances ( in Poly gala glochidiata, Stellaria gloohidiata, and Limnanthemum nymphceoides) do these structures, which may be classed together as hooked bristles and hooked prickles, occur on the seeds themselves; usually they are appendages of the pericarp, and as such exhibit every degree of size p
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1895
