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Show 398 GEOGRAPHICAL DISTRIBUTION. CHAP. XII. almost every product of the Ian~ and wa ~er bears the unmistakeable stamp of the Amencan cont1nent. There are twenty·six land birds, and twenty·~ve of these arc ranked by Mr. Gould as distinct spec1es, s~pposed to have been created here; yet the close affin1ty of most f these birds to American species in every character, 0 f . . in their habits, gestures, and tones o vo1ce, was mani-fest. So it is with the other animals, and with nearly all the plants, as shown by ~r. Hoo~ter in his ~dmirable memoir on the Flora of th1s archipelago. 'Ihe naturalist, looking at the inhabitants of these volca.nic islands in the Pacific, distant several hundred miles from the continent, yet feels that he is standing on American land. Why should this be so ? why should the species which are supposed to have been created in the Galapagos Archipelago, and nowhere ~lse, bea~· so plain a stamp of affinity to th?~e crea t~d 1~ Amer1ca ? There is nothing in the cond1t1ons of life, 1n the geological nature of the islands, in their height or climate, or in the proportions in which the several classes are associated together, which resembles ~losely the co~ditions of the South American coast: 1n fact there 1s a considerable dissimilarity in all these respects. On the other hand, there is a considerable degree of resemblance in the volcanic nature of the soil, in climate, height, and size of the islands, between the Galapa~os and Cape de Verde Archipelagos: but what an ent~re and absolute difference in their inl1abitants ! The Inhabitants of the Cape de Verde Islands are related. to those of Africa, like those of the Galapagos to Amenca. I believe this grand fact can receive no sort of explanation on the ordinary view of independent creat1?n; whereas on the view here maintained, it is obvwus that the Galapagos Islands would be likely to receive colonists, whether by occasional means of transport or CIIAP. XII. OCEANIC ISLANDS. 399 by formerly continuous land, from America; and the Cape de Verde Islands from Africa ; and that such colonists would be liable to modification ;-the principle of inheritance still betraying their original birthplace. Many analogous facts could be given: indeed it is an almost universal rule that the endemic productions of islands are related to those of the nearest continent, or of other near islands. The exceptions are few, and most of them can be explained. Thus the plants of ICerguelen Land, though standing nearer to Africa than to America, are related, and that very closely, as we know from Dr. I-Iooker's account, to those of America: but on the view that this island has been mainly stocked by seeds brought with earth and stones on icebergs, drifted by the prevailing currents, this anomaly disappears. New Zealand in its endemic plants is much more closely related to Australia, the nearest mainland, than to any other region: and this is what might have been expected; but it is also plainly related to South America, which, although the next nearest continent, is so enormously remote, that the fact becomes an anomaly. But this difficulty almost disappears on the view that both New Zealand, South America, and other southern lands were long ago partially stocked from a nearly intermediate though distant point, namely from the antarctic islands, when they were clothed with vegetation, before the commencement of the Glacial period. The affinity, which, though feeble, I am assured by Dr. Hooker is real, between the flora of the south-western corner of Australia and of the Cape of Good Hope, is a far more remarkable case, and is at present inexplicable : but this affinity is confined to the plants, and will, I do not doubt, be some day explained. The law which causes the inhabitants of an archi- |