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Show 298 IMPEltFECTION OF THE CHAr. IX. yet are far more closely allied. to each other than are the species found in more w1dely separated ~ormations ; but to this subject I shall have to return 1n the following chapter. . . . One other consideration is worth notice : w1th animals &nd plants that can propagate rapidly and are not highly locomotive, there is reason to suspect, as we have formerly seen, that their varieties are generally at fi~st iocal · and that such local varieties do not spread ~idely and supplant their par~nt-forms unt~l they have been modified and perfected 1n some considerable degree. According to this view, the chance of discovering in a formation in any one country all the early stages of transition between any two forms, is small, for the successive changes are supposed to have been local or confined to some one spot. Most marine animals have a wide range ; and we have seen that with plants it is those which have the widest range, that oftenest present varieties ; so that with shells and other marine anip1als, it is probably those which have had the widest range, far exceeding the limits of the known geological formations of Europe, which have oftenest given rise, first to local varieties and ultimately to new species ; and this again would greatly lessen the chance of our being able to trace the stages of transition in any one geo .. logical formation. It should not be forgotten, that at the present day, with perfect specimens for examination, two forms can seldom be connected by intermediate varieties and thus proved to be the same species, until many specimens have been collected from many places; and in the case of · fossil species this could rarely be effected by pa~re ... ontologists. We shall, perhaps, best perceive th~ Improbability of our being enabled to connect spemes.by numerous, fine, intermediate, fossil links, by asking CHAP. IX. GEOLOGICAL RECORD. 299 ourselves _whet~er, for instance, geologists at some future penod Will be able to prove, that our different breeds o~ cattle, sheep, horses, and dogs have descended from a ~Ingle stock or fro:r_n several aboriginal stocks ; or, again, whether certain sea-shells inhabiting the shores .of N ort~ ~merica, which are ranked by some concholo~ Ists as distmct species from their European representatives, and by other conchologists as only varieties a:e . really varieties or are, as it is called, specificall; dis~1nct: Thi~ co~ld be e~ected only by the future geologist discovenng In a fossil state numerous intermediate gradations; and such success seems to me improbable in the highest degree. Geological research, though it has added numerous ~pecies to existing and extinct genera, and has made the Intervals between some few groups less wide than they ot~er~se woul~ have been, yet has done scarcely anything In b~eaking down the distinction between species, by connecting them together by numerous, fine, inter~ ediate varieties; and this not having been effected, Is probably the gravest and most obvious of all the many o~ject~ons which may be urged against my views. Hence 1t will be w~rth ':hile ~o sum up the foregoing rema:ks, un~er an Imaginary illustration. The Malay Archipelago 1s of about the size of Europe from the North Cape to the Mediterranean, and from Britain to ~ussia ; ~nd therefore equals all the geological formations ~hich have been examined with any accuracy, excepting those of the United States of America. I fully agree with Mr. Godwin-Austen, that the present condition of the Malay Archipelago, with its numerous large islands separated by wide and shallow seas, probably represents the .former state of Europe, when most of our formations were accumulating. The Malay Archipelago is one of the richest regions of the |