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Show EXPLANATIONS. negative at the best; and it says as rnuch for the non .. preservation of mosses and other humble plants as for dicotyledons. It ha!3 also been remarked that, consider~ ~ng such facts as the disappearance of equisetum hyemale In water, a plant containing an unusual quantity of silex, "the proportion of fossil plants in each formation must depend on other circumstances besides their power of re. ~:~isting decomposition."* "Too much importance has," in the opinion of the author of this observation, "been attached to Dr. Lindley's experiments." The British Quarterly Review says-" The author admits there were dicotyledons among these plants, and C!oes not see that, however few they 1nay be, it entirely upsets the theory of progressive advanc.e, especially in the absence of any proof as to whether they were created first or last." This proceeds, as do many similar objections, upon the idea that a formation represents one point in time. A formation, in reality, represents many years, or rather ages. Such expressions as that simple and complex plants occur together in the carboniferous formation, or even (shall we say) in its first fossil bands, are vague expressions, perhaps conveying an idea substantially false. There is no such precision in the ascertained relations o(.fossils to particular strata, as to entitle any one to say that the simple and complex plants of this formation are rigidly contemporaneous. They may have followed each other within the space of half a century in a particular region, and yet been preserved in but one stt·atutn, o1· little group of st·rata. The actual appearances of the carboniferous formation thus, perhaps, allow full titne for a progressive advance in particular regions, from the fleshy luxuriant plants of the marsh and low sea rnargin to the robust tree of the more elevated regions. We must remember, too, that the vegetation o! the carbonigenous era, even if we take it back to include the confer said to have lately been found in the Old Rea of Cromarty, or the fern leaf of the Silurians, was preceded by unequivocally simple plants in the fucoids. Starting with these, and finding the first great burst ol land vegetation composed mainly of low cryptogamic an1l monocotyledonous plants,-finding, moreover, the ex· c eptions chiefly of the intei·mediate character, and that • Mr. C. J. Bunbury, at the British Association, 1945; Athen•· um's Report. :FOSSILS OF THF PERMIAN SYSTEM 23~ ~he dicotyledons increase afterwards while the of.hers decline,- we cannot well resist the conclusion, that we see the traces of a progress in the history of this kingdom of nature. It may be less clear than we could wish ; but such light as we have certainly favors the development theory. We now come to the Magnestan Limestone deposit, latterly called the Permian s -yste1n. At this place, the Edinburgh reviewer introduces some general observations, which I hope he will yet acknowledge to be unjust, as I am sure the whole of his substantive charges are. " It may be true," he says, " that sea-weeds came first, but of this we have no proof." How a good geologist can have allowed himself to speak in this manner, even in eagerness to theorize against theory, I am quite at a loss to under~tand, for the positive facts of the occurrence of fucoids in the Lower Silurians, and of the very first traces of land vegetation in subsequent formations, are as palpable and undoubted as he himself acknowledges the precedence of fish by invertebrata to be; nor has any one ever pretended to expect that land vegetation ·would be found earlier than the tnarine. I have here ventured no conjecture of my own, but only spoken as all the geolo gical books teach. " Of land plants," he continues, " we have not the shadow of proof that the simpler forn1s came into being before the more complex.'' The reader has just been told upon undoubted authority that, in the first great show of land vegetation, talnng such positive evidence as we have, the simple forms are vastly more numerous than the complex. Finding that we have first ample marine vegetation, then a land vegetation in which the plants, with only a small exception, are cellular and cryptogamic, while of the exception a very small number are dicotyledonous, and a conspicuous group (the conifers) intermediate-! feel that I am entitled to say that positive evidence speaks for a precedence of high but simple forms; which is what I have done. "It is true,'~ thus proceeds the reviewer, " that we see po1ypiaria, crinoidea, articulata, and mollusca; but it is not true that we meet with them in the order stated by our author." It is humiliating to have to answer an objection so mean. There is no Htatement that the animals came in this order. I have only put the words into this arrangement, in accordance with the custom now commonly followed of observing the |
