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he has discovered the group of the Simocyonidæ intermediate between bears and wolves; the genus Hyænictis which connects the hyænas with the civets ; the Ancylotherium, which is allied both to the extinct mastodon and to the living pangolin or scaly ant-eater; and the Helladotherium, which connects the now isolated giraffe with the deer and antelopes.
Between reptiles and fishes an intermediate type has been found in the Archegosaurus of the Coal formation; while the Labyrinthodon of the Trias combined characters of the Batrachia with those of crocodiles, lizards, and ganoid fishes. Even birds, the most apparently isolated of all living forms, and the most rarely preserved in a fossil state, have been shown to possess undoubted affinities with reptiles; and in the Oolitic Archæopteryx, with its lengthened tail, feathered on each side, we have one of the connecting links from the side of birds; while Professor Huxley has recently shown that the entire order of Dinosaurians have remarkable affinities to birds, and that one of them, the Compsognathus, makes a nearer approach to bird organisation than does Archæopteryx to that of reptiles.
Analogous facts to these occur in other classes of animals, as an example of which we have the authority of a distinguished paleontologist, M. Barande, quoted by Mr. Darwin, for the statement, that although the Palæozoic Invertebrata can certainly be classed under existing groups, yet at this ancient period the groups were not so distinctly separated from each other as they are now ; while Mr. Scudder tells us, that some of
the fossil insects discovered in the Coal formation of America offer characters intermediate between those of existing orders. Agassiz, again, insists strongly that the more ancient animals resemble the embryonic forms of existing spècies; but as the embryos of distinct groups are known to resemble each other more than the adult animals (and in fact to be undistinguishable at a very early age), this is the same as saying that the ancient animals are exactly what, on Darwin's theory, the ancestors of existing animals ought to be; and this, it must be remembered, is the evidence of one of the strongest opponents of the theory of natural selection.
Conclusion. I have thus endeavoured to meet fairly, and to answer plainly, a few of the most common objections to the theory of natural selection, and I have done so in every case by referring to admitted facts and to logical deductions from those facts.
As an indication and general summary of the line of argument I have adopted, I here give a brief demonstration in a tabular form of the Origin of Species by means of Natural Selection, referring for the facts to Mr. Darwin's works, and to the pages in this volume, where they are more or less fully treated.
A Demonstration of the Origin of Species by Natural
NECESSARY CONSEQUENCES (afterwards taken as Proved Facts).
RAPID INCREASE OF ORGAN
STRUGGLE FOR EXISTENCE, ISMS, pp 29, 265; (“Origin
the deaths equalling the of Species,” p. 75, 5th Ed.)
births on the average, p. 30; TOTAL NUMBER OF INDIVI
(“Origin of Species," chap. DUALS STATIONARY, pp. 30,
III.) 266. STRUGGLE FOR EXISTENCE.) SURVIVAL OF THE FITTEST, HEREDITY WITH VARIATION, or Natural Selection; mean.
or general likeness with ing simply, that on the individual differences of pa whole those die who are rents and offspring, pp. least fitted to maintain their 266, 287-291, 308; (“ Origin existence; (“Origin of Speof Species,” chap. I., II., V.) cies," chap. IV.)
CHANGES OF ORGANIC FORMS,
to keep them in harmony with the Changed Condi
tions; and as the changes SURVIVAL OF THE FITTEST.
of conditions are permaCHANGE OF EXTERNAL CON
nent changes, in the sense DITIONS, universal and un
of not reverting back to ceasing. — See “ Lyell's
identical previous condi. Principles of Geology."
tions, the changes of organic forms must be in the same sense permanent, and thus originate SPECIES,
THE DEVELOPMENT OF HUMAN RACES
UNDER THE LAW OF NATURAL SELEC-
Among the most advanced students of man, there exists a wide difference of opinion on some of the most vital questions respecting his nature and origin. Anthropologists are now, indeed, pretty well agreed that man is not a recent introduction into the earth. All who have studied the question, now admit that his antiquity is very great; and that, though we have to some extent ascertained the minimum of time during which he must have existed, we have made no approximation towards determining that far greater period during which he may have, and probably has existed. We can with tolerable certainty affirm that man must have inhabited the earth a thousand centuries ago, but we cannot assert that he positively did not exist, or that there is any good evidence against his having existed, for a period of ten thousand centuries. We know positively, that he was contemporaneous with many now extinct animals, and has survived changes of the earth's surface fifty or a hundred times greater than any that have occurred during the historical period; but we cannot place any definite limit to the number
of species he may have outlived, or to the amount of terrestrial change he may have witnessed.
Wide differences of opinion as to Jan's Origin. But while on this question of man's antiquity there is a very general agreement,—and all are waiting eagerly for fresh evidence to clear up those points which all admit to be full of doubt,-on other, and not less obscure and difficult questions, a considerable amount of dogmatism is exhibited ; doctrines are put forward as established truths, no doubt or hesitation is admitted, and it seems to be supposed that no further evidence is required, or that any new facts can modify our convictions. This is especially the case when we inquire,–Are the various forms under which man now exists primitive, or derived from pre-existing forms; in other words, is man of one or many species ? To this question we immediately obtain distinct answers diametrically opposed to each other : the one party positively maintaining, that man is a species and is essentially one—that all differences are but local and temporary variations, produced by the different physical and moral conditions by which he is surrounded; the other party maintaining with equal confidence, that man is a genus of many species, each of which is practically unchangeable, and has ever been as distinct, or even more distinct, than we now behold them. This difference of opinion is somewhat remarkable, when we consider that both parties aru well acquainted with the subject; both use the same