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Show 284 EXPLANATIONS. that is to say, it has been dry land for a much less s:~ac6 of ti1ne, though one still considerable. What are the organic productions of this curious archipelago f ln the first place, they are " mostly aboriginal creations, found nowhere else," though with an affinity to those of America. Many of them are even peculiar to particular islands in the group. But the remarkable fact bearing on the present inquiry is, that, excepting a rat or a mouse on two of the islands, supposed to have been imported by foreign vessels, there are no mammals in the Galapagos. The leading terrestrial animals are ~eptiles, and these exist in great variety, and in some instances of extraordinary size. Lizards and tortoises particularly abound. There are also birds, eleven kinds of swimmers and waders, and twenty-six purely terrestrial. All this harmonizes \vith our ideas of the world in general at the time of the oolites. It speaks of time b~ing necessary for the completion of the animal series in any scene of its development. The Galapagos have not had the full time required for the completion of the series, and it is incomplete accordingly.* The entire harmony of this ""In the Vestiges, Australia is spoken of, for the same reason, as apparently a new country, one which has been belated in its physical and organic development. "\Ve have thera an order, or what 1s called an order, of mammals, namely, the marsupialia, besides a few monotremata; all of which may l>e regarded as only mammalian apices of certain bird families. 'l'he placental mammalian are wholly wanting. One might. uppose that the reasoning on which the comparative recentnes of this continent was inferred would .o.ave been readily intelligible, and that not even the most ingenious pervPrseness of oppo ition could have hung a remark upon it. Yet the ~~dinburgh Reviewer pr sent a note {p. 58), stating tl~at, on my own scheme of nature, 1 ·ew Holland ought to have been con, idered as one of the oldest countries. "He might have argu€'d (from its flora, its cestraceonts, it trigonim, and its marsupials) thal it was as old as our oolite~; but this would not have served the good ends of the scheme of development. An amusing ex~m· p:e of incon. istency." By old, r presurne, is hrre meant duratwu in the condition of dry land. I thoroughly agree ·..vith the \-Vestminster Review, when it says of this passage, "A more complete mi ·comprehension of reasoning we have never met with." Assu. - redly it may w 'll be held up. a that Review holds it, "as a warnina to believers in exparte criticism." The fact is, since, as Pro· fe~sor Phillips admit , t_herc hn been no brt>al in the.chain ot life from the beginning, our other continents, whate~er m1nor chang:es they may have undergone, have continued without an:y: cnt.1:e submergence in~e at least the commencement of tcrrcstnal bfe. Th 'Y a~·c therefore D cr than Au tralia could be presumed to l'e• ~vea upo'n the pti;lciplc hint~d at by the Bdinburgh reviewer. ZOOLOGY OF GALAPAGOS ISLANDS 285 fact does, I must confess, strike my mind fore ibly. Had there been rnammals and no reptiles, it would have been quite different. We should then have said that one de-:cided fact against the development theory had been ascer. tained. A minor circumstance in the zoology of these islands is worthy of note. The swimming and wading birds arc less diverse from those of the rest of the world than the terrestrial species, all of which but one are decidedly peculiar. The same holds good regarding the shells and the insects. Here we have the terrestrial an· imals spreading out into numerous variations, according to the greater variety and the more peculiar character of the circumstances determining their organjzation. * Mr. Darwin has likewise observed such facts in the natural history of solitary islands, as induce hirn to express his belie( that "the waders, after the innurnerable web-footed species, are generally the first colonists of small islands.'" It is his supposition that the birds in those instances are immigrants; but I must advert to the fact, as strikingly in harmony with my hypothesis of developinent, which '-'ras certainly formed without any knowledge of this illustration. Another mode of proof in the difficult circumstances with which we are dealing, is to shmv that the hypothesis will account, on a principle of law, for certain facts ~hich we ~ust otherwise suppos~ to be wholly capriCious and accidental. The hypothesis is, that, as a general fact, the progress of being in both kinds has been from th~ sea towards the land. Marine species of plants and animals are supposed to be, in the main, the pro()"enitors of terrestrial species. Life has, as it were, crept o~t ·of the sea upon the land. This, of course, leads us to consider the distribution of vegetable and animal forms in the ~e~, and the effect which these may have had in determ~ ning the Flora and Fauna of particular detached prov 1nces. We would necessarily suppose that any particu· ~ut is not that _Pr~nciple ut~erly absurd, implying as it does that hfe had ~tood st1.ll m A.ustralta at one ~oint, while 1t was advancing to the h1ghest forms m other cou ntrws 1 Nay that the agencies employed in .the formation of rocks had been' stopped there, for perhaps a third of the time of the earth's existence? The note would not be vV?rth.Y of this analysis, but that the self.compla~ ency o~ the wnter Is so apt to impose upon reac£r'i who do not mqmre for themselves. ~'See Darwin's .Journal ot a Voyage Round the \Vorld, c. xvii. |