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Show [CHAP. XI. GEOGRA.PUICA.L UISTRIBUTION. 316 d beet germinated after millet canary, hemp, clover, an enty-one hours in the ·n' been from twelve to tw . and two seeds of ~:O~a~hs of differe~t birds 0~~;e;eiained for two days beet grew after having .b:~~ater fish, I find, eat seeds of and fourteen hours. Fl e ts . fish are frequently devoured many land and water P an a' might be transported from b birds and thus the sdee s y kinds of seeds into the plYa ce to ' p 1a ce. I force d mthaenn gave the·u b od l' es t o fi ~h - stomachs of dead fish, an li ns . these birds after an ln-ing- eagles, storks, and ~~h~: rejected the seeds in pellets terval of many hours,. el ment . and several of these or passe d the m in thmr excfr e ermin' ati.o n C ert a1. n see d s, seeds retained their po~1~ed ~ this proc~ss. however, were always k I d feet of birds are generally Although the bea s t~~t earth sometimes adhe_res to quite clean, I c~n show removed twenty-two grams ~f them . in one Instance I ~oot of a partridge, and In d.r y ar' gi.l laceous eart h frobmb loe nqeu 1i1 te as large as the see d of this earth there wa~ a p~ ht occasionally be transporte~ to a vetch. Thus see s m g £ ts could be given showing great distances ; for mahy a~ s charged with seeds. Rethat soil almost everyh er~ll~ons of quails which annualfleet for a momen~ on t e r:~ and can we doubt that the ly cross th~ Medlthr:a£eat ~ould sometimes inc}ude a fe~ earth adhel'lng toBt elr ~ell presently have to recur to thls minute seeds~ ut s a subject. to be sometimes loaded with As icebergs are known n carried brushwood, bones, earth and stones, and f~Yd_ ele can hardly doubt that they and the nest of a lan - Ir ' ted seeds from one part to must occasionally h~ve trdn:~~:rctic regions, as suggeste~ another of the d~rc~lc ~~ Glacial period from one part o by Lyell ; and urmg . e another. In the Azores, the now temperate regioru; to . es of plants common from the large numb~r of t~h ~t=~lants of other oceanic to Europe, in comparlSOD; Wl d and (as remarked by ::Mr. islands nearer to the roainlan 'h t northern character of H. C. Watson) fron; the ~omew latitude, I suspected that the flora in comparison Wlt\ th~ ked by ice-borne seeds, these islands ha<! beep. part y s oc 4JRAP. XI.] MEANS OF DISPERSAL. 317 during the· Glacial epoc~. ~t my request Sir C. Lyell wrote toM. Hartung to Inquire whether he had observed erratic boulders on these islands, and he answered that he had found large fragments of granite and other rocks which .do not oc?ur in the archipelago. l-Ienee we may safely Infer that Icebergs formerly landed their rocky burthens on the shores of these mid-ocean islands and it is at least possible that they may have brought' thither the seeds of northern plants. Considering that the several ~bove. means of transport, and that several other means, which Without doubt remain to be ~iscovered, have been in action year after year, for centuries and tens of thousands of years, it would I think be a marvellous fact if Inany plants had not thus become widely transported. These means of transport are sometimes called accidental, but this is not strictly correct: the currents of the sea are not accidental, nor is the direction of prevalent gales of wind. It should be observed that scarcely any means of transport would carry seeds for very great distances ; for seeds do not retain their vitality when exposed for a great length of time to the action of sea-water; nor could they be long carried in the crops or intestines of birds. These means, however, would suffice for occasional transport across tracts of sea some hundred miles in breadth, or from island to island, or from a.contine:rit .to a neighbouring island, but not from one distant contJnent to another. The .floras of distant continents would not by such means become mingled in any great degree ; but would remain as distinct as we now see them to be. The currents, from their course would . never ~ring seeds fro~ North America to Britain,'though they llllght and do bring seeds from the West Indies to our 'Yest~rn shores, where, if not killed by so long an immerswn 1n salt-water, they could not endure our climate. Almost every year, one or two land-birds are blown across the whole Atlantic Ocean, from North America to the Western shores of Ireland and England ; but seeds could be trans:port~d by these wanderers only by one means, namely, .In dirt sticking to their feet, which is in itself a rare acc1dent. Even in this case, ho'v small would the |