state of physical condition, of social aggregation, or of mental and moral cultivation, and are therefore to be considered as illustrations of the law that "all imperfection must disappear," it can scarcely be contended that those nations or communities which have either remained stationary or have degenerated are illustrations of the same law. Yet history abounds with such instances. In some Eastern nations, notably in China, there is comparatively little change of any kind within historic periods; probably no one would be likely to see there any indications of the evanescence of evil; and yet China and its dependencies may be supposed to contain nearly half, certainly more than one-third, of the population of the earth. It is not necessary to enter into any details as to degenerations; their history is the history of all nations that have risen and fallen again; where "unfitness to the conditions of existence" has resulted in decay rather than in progress. This digression from the main subject of this inquiry has been introduced with the object of showing what care it is necessary to exercise in examining doctrines like these, set forth with much confident use of language, before accepting them as valid. Further illustrations will occur as we proceed. In the preceding paper* the evidence for the first of the three propositions concerning the origin of organic forms was investigated-viz., "That the earliest organisms were the natural product of the interactions of ordinary inorganic matter and force." It appeared to be a result of the inquiry that neither observation, experiment, nor reason, gave any testimony in favour of such a view; and that life was in all cases due either to antecedent life, or to a power or force from without that was not identical, nor correlated, with the ordinary physical forces. The two remaining propositions which now claim attention are more conveniently combined in one for discussion, and may be thus formulated:-"That all the forms of animal and vegetable life, including man himself, have been successively and gradually developed from the earliest and simplest -organisms." A casual survey of the vegetable and animal world exhibits to the inquirer an infinite number of forms, having almost every conceivable variety of general aspect and attribute; whilst a closer investigation shows certain relationships of type and function to subsist amongst certain members. Individuals are closely grouped together with such identity of structure, and such constancy of character derived from parent to offspring, as to be ranked as species. Various species present such analogies one to the other as to be classed under more extended heads, as genera. Genera, again, that are allied by certain affinities, are united to * See CONTEMPORARY REVIEW for October. form natural orders; and these are grouped again, according to such general characters as they may possess in common, into classes and sub-kingdoms. Thus all the varieties of our domestic dog or cat are so alike in essential structure, that they are respectively considered as distinct species. But the dog has many points of resemblance to the wolf, the dingo, &c.; and the cat has similar relations to the lion, tiger, and puma. The allies of the dog are therefore united to form a family, called Canis; and those of the cat are similarly united into the family Felis. But the Canida and the Felida are again allied by important points of structure, food, and habits to each other and to the bears (Ursidae), martens (Mustelide), and seals (Phocida); and these families are aggregated to constitute the natural order of the CARNIVORA. These form one of the great divisions of the class MAMMALIA-a section of the great sub-kingdom of the VERTE BRATA. Up to a comparatively recent period, the majority of naturalists held, with regard to these divisions, that only the members of what were called species (such as were fertile together, and had fertile offspring), had any true alliance, any blood-relationship; and that a family, a genus, an order, or a class, was simply an ens rationis, a mental classification for convenience only. But so early as 1796, Goethe alluded to the development of the higher animals, and man himself, from lower forms of life; and in 1807 he somewhat expanded the idea, with references to embryology. He was soon followed by Oken, who, as we have before seen, claims "a kind of inspiration," but whose inflated. dogmatism presents few tangible. points for either intelligent acquiescence or dissent. His doctrine as to organisms is as follows: (900) Every organic has issued out of mucus." (901) "The primary mucus out of which everything organic has been created is the sea-mucus." (905) "The sea-mucus, as well as the salt, is produced by the light. Light shines upon the water, and it is salted. Light shines upon the salted sea, and it lives." (906) "All life is from the sea, none from the continent." (912) "The first organic forms, whether plants or animals, emerged from the shallow parts of the sea." (913) "Man also is a child of the warm and shallow parts of the sea in the neighbourhood of the land." (930) "The primary organic is a mucus point." (934) "The first organic points are vesicles." (958) "No organism has been created of larger size than an infusorial De Maillet's Telliamed was published almost fifty years before, in 1748; but except as indicating some belief in the variability of species, it requires little notice as a philosophical work. The figures refer to the sections in the Ray Society's edition of Oken's PhysioPhilosophy. point. No organism is, nor has one ever been, created which is not microscopic." (959) Whatever is larger has not been created, but developed." (960) Man has not been created, but developed." Oken, it will be seen, allows the existence of a Creator, whose function is to create microscopic points. Philosophers are wiser now. Lamarck followed in 1815 with some daring speculations, which I venture to think were indefinitely more philosophical* than any of the theories of evolution which have been propounded since that time, inasmuch as they had some basis in physiological truth. But it is unnecessary now to notice these doctrines at any length, since it is at the present time generally believed that "there is but one hypothesis as to the origin of species of animals in general which has any scientific existence-that propounded by Mr. Darwin." That hypothesis is too well known to require any extended introduction, but may be briefly stated thus:Owing to the high geometrical rate of increase of each species, there is a constant struggle for life going on amongst all living creatures, in which struggle the "weakest go to the wall," and the strongest, that is, the "favoured races," survive. These favoured races are so favoured in virtue of their having been born (in obedience to chance, or some law the conditions of which are unknown) with a structure in so far differing from that of their species, as to afford them an advantage, however slight, over their brethren in the said struggle. This is innate variability; and when a variation occurs, thus enabling its possessor to survive where others die, there is a prospect of a race being formed with this peculiarity, which, slowly augmenting for thousands of generations, at last gives character to a new species. And the slow accumulation, through countless ages, of similar modifications, by natural selection, forms distinct genera and orders. The same powers which we daily see producing what we call varieties are on this theory capable of producing species in longer periods, and in still more extended periods, genera, orders, and classes. There are thus three essential elements in this theory-variability, struggle for existence, and natural selection-and by means of these, it is supposed that, beginning with the monera (which was evolved from inorganic matter), we have in the course of long ages obtained all the forms of life that have ever appeared on our globe, including man, without the "intrusion" of any creative power. It is not my intention to attempt any detailed investigation of these views. This has been done so often by far abler hands than Lamarck's account of the development of the giraffe's long neck is infinitely more practical and probable than Mr. Darwin's; as well as his general, though perhaps komewhat vague, ideas of the production of various other structures by means of attempted and increased function, or desire for action. † Professor Huxley's Man's Place in Nature, p. 106. mine, that it would appear as though nothing more could be said by friend or foe without mere repetition. What can be done by a calm and highly cultivated critical faculty, a profound knowledge of natural history and of all biological science, and a clear logical reason, to refute the fallacies of natural selection, has been done by Mr. St. George Mivart in his "Genesis of Species," and later in his "Lessons from Nature." But the theory has a source of vitality which does not lie in the domain of facts or reason, and will therefore doubtless survive for a time. There are, however, a few general considerations upon which I think due stress has not been laid, tending to indicate that this hypothesis "does not really exist, although it may seem to do so," as was said by a distinguished writer concerning another theory— in other words, that it has no scientific basis. The first is thisthat the hypothesis of natural selection is not directly supported by any single fact in the whole range of natural history or palæontology; but that on the other hand every fact which is known with any certainty in those sciences, so far as it bears upon natural selection, directly opposes it. In adducing evidence of these positions I will neither give my own observations, nor those of any opponent of the theory, but will call upon its friends and supporters to bear their testimony, first, as to the evidence for the succession of life upon the earth from lower to higher forms; and, secondly, as to the existence of any instance of conversion of one species into another. Professor Huxley, whose authority in all matters of natural history and paleontology is indisputable, and who cannot be suspected of any antagonism to Evolution in general, or to Mr. Darwin's views in particular, thus writes in 1862 :— "What, then, does an impartial survey of the positively ascertained truths of paleontology testify in relation to the common doctrines of progressive modification, which suppose that modification to have taken place by a necessary progress from more to less embryonic forms, or from more to less generalized types, within the limits of the period represented by the fossiliferous rocks? "It negatives those doctrines, for it either shows us no evidence of such modification, or demonstrates it to have been very slight; and as to the nature of that modification, it yields no evidence whatsoever that the earlier members of any long-continued group were more generalized in structure than the later ones. Obviously if the earliest fossiliferous rocks now known are coëval with the commencement of life, and if their contents give us any just conception of the nature and extent of the earliest fauna and flora, the insignificant amount of modification which can be demonstrated to have taken place in any one group of animals or plants is quite incompatible with the hypothesis that all living forms are the Mr. Mivart's final verdict is as follows:-" With regard to the conception as now put forward by Mr. Darwin, I cannot truly characterize it but by an epithet which I employ with great reluctance. I weigh my words, and have present to my mind the many distinguished naturalists who have accepted the notion, and yet I cannot hesitate to call it a puerile hypothesis."-Lessons from Nature, p. 300. results of a necessary process of progressive development, entirely comprised within the time represented by the fossiliferous rocks. "Contrariwise, any admissible hypothesis of progressive modification must be compatible with persistence without progression through indefinite periods."* This momentous judgment was somewhat revised in the anniversary address to the Geological Society in 1870. It was fully confirmed "so far as the invertebrata and lower vertebrata are concerned;" but it was to some extent modified in reference to the higher vertebrata, where there seemed to be "a clear balance in favour of the evolution of living forms one from another"—this with sundry qualifications. The learned writer gives it also as his opinion that should such an hypothesis as that of progressive modification "eventually be proved to be true," the only way in which it can be demonstrated will be "by observation and experiment upon the existing forms of life."t With regard to the second point in question, the transmutation of species, the same authority writes thus: "After much consideration, and with assuredly no bias against Mr. Darwin's views, it is our clear conviction that as the evidence stands it is not absolutely proven that a group of animals, having all the characters. exhibited by species in nature, has ever been originated by selection, whether artificial or natural."+ This was written in 1860; it was confirmed in 1863, in the essay on "Man's Place in Nature;" and up to the present time. the evidence stands exactly where it did; observation and experiment alike having hitherto failed to make evident the slightest approach towards specific transmutation. Notwithstanding which, Professor Huxley now declares that Evolution, which was once “a matter of speculation and argument," has now "become a matter of fact and history. The history of Evolution, as a matter of fact, is now distinctly traceable. We know it has happened, and what remains is the subordinate question of how it happened."§ Again, on the other hand, it has been clearly demonstrated that certain specific forms of life have remained absolutely unchanged during immeasurable periods of time, even since the chalk period. Professor Huxley says "The Globigerina of the present day, for example, is not different specifically from that of the chalk; and the same may be said of many other Foraminifera. I think it probable that critical and unprejudiced examination will show that more than one species of much higher animals have had a similar longevity; but the only example which I can at present give Essay on Persistent Types of Life, in Lay Sermons, p. 225. § Address at Buffalo, August 25th. Lay Sermons, &c., p. 295. |