Vestiges of the Natural History of Creation With a Sequel

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\ EXPLANATIONS. iar Flora or Fauna occupying a certain ~eographical area in the ocean would be apt to become tr.e comm?~ s_ource of the Flora or Fauna of any masses of land adJOining to it. Now we shall see how the facls harmonize with this view. Wherever there is a group of islands standing much apart, its plants and animals are never fo~nd ~llied to those of any rernote region of the earth, but Invanably show an affinity to those of the nearest larg~r .masses of hmd. Thus, for example,. the Galapagos e~h1b1t general characters in common with South America; the Cape de Verd islands with Africa. They are, in Mr. Darwin's happy phrase, ~atellites to those continents in respect of natural history. Again, when masses of lan~ are only divided from each other by narrow seas, ther~ Is usually a community of forms. The European and Afncan shores of the Mediterranean present an example. Our own islands afford another of far higher value. It appears that the flora of Ireland and Great Britain is various, or rather that 've have five floras, or distinct sets of plants, and that each of these is partaken of by a portion of the oppo­site continent. There are, 1st, a flora confined to the west of Ireland, and imparted likewise to the north-west of Spain· 2d a flora in the south-west promontory of England ~nd ~f Ireland, extending across the Channel to the north-west coast of France; 3d, one common to the south-east of England,.and north of.France ~ 4th, an.Al­pine flora developed In the cotbsh and Welsh High­lands and intimately related to that of the N orweg1an Alps~ 5th a flora which prevails over a large part of En~l~nd a~d Ireland, " mingling with the other floras, and diminishino- thouo-h slightly, as we proceed west ward·'' this bebar' s intinm ate relati. ons w1. t h t h e fl ora or Germ~ny. Facts so. remarkab~e wou.ld force the.me:est fact-collectot· or spectes-den )minator Into generahzatwn The really ingenious man who late.ly brouo-ht.them under notice,* could only urmise, as their explanattOn, that the spaces now occupied by the intermediate seas must have oeen dry land at the time when these floras were created. In that case, either the original arrangements of the floras, or the selection of land for ubmero-ence, must have been apposite to the case in a degt~ee far. from usu~l.. The n~­cessity for a sirnpler cau~c IS obvious, and It IS found 1n • See a paper, read by Professor Edv.·ard Forbes, at Cambridge • :une, l8:lf), in Literary Gazette, No. 14 1 GEOGRAPHICAL DIS'rRIBUTION OF PLANTS. 287 the hypothesis of a spread of terrestrial vegetation from the sea into the lands adjacent. The community of forrns in the various regions opposed to each other merely indi­cates a distinct marine creation in each of the oceanic areas respectively interposed, and which would naturally advance into the lands nearest to it as far as circumstances of soil and climate were found agreeable.* There is still the difficulty of accounting for the orig­Htation of the first forms of life in the various lines after­wards pursued to a high development. How was the in­organic converted into the first rudiments of the organic? Whence, and of what nature was the impulse that first kindled sensation and intelligence upon this sphere? A suggestion on these subjects is hazarded in my book; but though we were to consider the matter as an entire mys­tery, it is, after all, only so in the same degree, and to the same effect, as the c~mmencement of a new being from a little germ is a mystery to us, although we know that it is one of the most familiar of all natural events. This last marvel we know to be under natural law, though we can­not otherwise explain it. If we can regard the origin and development of life upon our planet as having been equally under natural law, the .whole point is gained; for we are not so much inquiring in order to say how? as was it within or beyond the natural? We have seen, then, as I conceive, that · all the associated truths of science go to this point. The whole concur to say, that to believe an exception in this particular of the history of nature, is an absurdity. Difficulties there may be in treating the case positively; some facts of inferior impor­tance may seem to point to an opposite conclusion; but i·R the balance of the two sets of. evidences, those for a universality of natural law down-weigh the other beyond calculation. I have now to allude to a class of objections different from those made on scientific grounds, but fortunately not ,. It is, perhaps, hardly necessary here to advert to any explana­tion which might be brought from the diffusion of seeds by ocean currents, because the direr.tness of the opposition of the fields ot these floras to each other across the Channel is obviously incon· sistent with that idea. In such a case, the constituents of thP VR.· rious floras would have been confused amongst each other by tht." diversity of currents in the intermediate seas. Mr. Forbes plainly confesses this explanation to be inadmissible in the present case i and, of course, it is not the right explalilatioil. in an:"· other .