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Show 78 AGENCY OF ANIMALS [Ch. V. . h an alluvial soil on wh l.C h herbs and pine bergs covered w1t . h' h ften continue to vegetate growmg, w lC o saplings are seen h the ice-island is stranded. on some distant shore w ere t' the seeds being in their t t marine vegeta wn, With respec 0 • • d in water without injury t Y remam 1mmerse .. native elemen 'rna h . 0 difficulty in concelVmg . . ds so that t ere lS n for indefimte perw ' genial climates, contrary . f · wherever uncon the diffuswn o species d not interfere. All are familial' currents, and other causes~ o 'th the siO'ht of the floatmg sea-weed Wl o '1 k n ocean's foam to sal ' " Flung from the roc o tem est's breath prevail.'' Where'er the surge may sweep, the p h 'd . f d 'ft eed occur on eac Sl e Remarkable accumulatwlns ? pn ci~ and Indian Oceans. t . · the At ant1c, a ' of the equa 01 m . 1 first encountered these C 1 b nd other navigators w lO o urn us 1a · th Nort1 1 ern Atlantl' c' compared them to banks. of a gre m e and state that they retarded the vast mundated. meadows, The most extensive bank is a little progress of thel~ d:essel;. Fa a1, one of the Azores, between west of the meil Ia~ o . 1 yt north winds sometimes prevail . d !e5 o d 86 · v1o en lat1tu e an . ' d to low latitudes, as far as in this space, and drlve the sea-wee the !e4th or even the !eOth degree*. f d l'k rece tacles in which the seeds o many The hollow po -I e P . h d t the seed-vessels 1 . 1 d()'ed and the filaments attac e o a gre ate o o ' • b ncr and we may observe of others, seem intended to glve uoyal ) 'z· so that the d h t in genera pro iferou8, that these hy rop y es are be developed into a perfect smallest fragment of a branch c~~hc greater number of species 1 t The seeds moreover, o d Pan • . ' atter like that which surroun s are enveloped with; l~:~~u:~ch not only protects them from the eggs of some s ' h t floating bodies or to rocks. injury, but serves to attach~ em o . onl of the fertile re· But we have as yet consldered patt y. f· their in seeds to a distance rom sources of nature for convey g . f . ls are busily place of growth. The various tnbes o hamdma. such im· engaged . .m furt h er·m g an ob ~' ect whence t ey en.v .e is found portant advantages. Sometimes an express provislon ,.. Greville, Introduction to Algoo Britannicre, P• 12. Ch.V.] IN DIFFUSING PLANTS. 79 in the structure of seeds to enable them to adhere firmly by prickles, hooks, and hairs, to the coats of animals, or feathers of the winged tribe, to which they remain attached for weeks, or even months, and are borne along into every region whither birds or quadrupeds may migrate. Linnreus enumerates fifty genera of plants, and the number now known to botanists is much greater, which are armed with hooks by which, when ripe, they adhere to the coats of animals. Most of these vegetables, he remarks, require a soil enriched with dung. Few have failed to mark the locks of wool hanging on the thorn-bushes, wherever the sheep pass, and it is probable that the wolf or lion never give chace to herbivorous animals without being unconsciously subservient to this part of the vegetable economy. A deer has strayed from the herd, when browsing on some rich pasture, when he is suddenly alarmed by the approach of his foe. He instantly plunges through many a thicket, and swims through many a river and lake. The seeds of the herbs and shrubs adhere to his smoking flanks, and are washed off again by the streams. 'rhe thorny spray is torn off and fixes itself in his hairy coat, until brushed off again in other thickets and copses. Even on the spot where the victim is devoured, many of the seeds which he had swallowed immediately before the pursuit may be left on the ground uninjured. The passage, indeed, of undigested seeds through the stomachs of animals is one of the most efficient causes of the dissemination of plants, and is of all others, perhaps, the most likely to be overlooked. Few are ignorant that a portion of the oats eaten by a horse preserve their germinating faculty in the dung. The fact of their being still nutritious is not lost on the sagacious rook. To many, says Linnreus, it seems extraordinary, and something of a prodigy, that when a field is well tilled and sown with the best wheat, it frequently produces darnel or the wild oat, especially if it be manured with new dung: they do not consider that the fertility of the sma1ler seeds is not destroyed in the ventricles of animals *. ! Linnoous, Amoon, Acad., vol, ii, p. 40~. |