It was to the section D. (Zoology and Botany, including Physiology, a sub-section attached for the last-named subject) that the chief interest attached at the late meeting of the British Association, in consequence of the popularity at the present moment of discussion as to the Origin of Species. After a Report by Dr. Ogilvie, intimating the little that has been done, in consequence of the tempestuous weather and the early meeting of the Association, by the Dredging Committee for the North and East Coasts of Scotland, and a very interesting communication by the Rev. P. P. Carpenter, on the Progress of Natural Science in the United States and Canada, Dr. Daubeny led off in the great question of the day, by a paper on the Final Causes of the Sexuality of Plants, with particular reference to Mr. Darwin's work on the Origin of Species by Natural Selection. [...]
 Professor Huxley deprecated any discussion on the general question of the truth of Mr. Darwin's theory. He felt that a general audience, in which sentiment would unduly interfere with intellect, was not the public before which such a discussion should be carried on. [ ... ] Professor Owen said that he wished to approach this subject in the spirit of the philosopher, and expressed his conviction that there were facts by which the public could come to some conclusion with regard to the probabilities of the truth of Mr. Darwin's theory. Whilst giving all praise to Mr. Darwin for the courage with which he had put forth his theory, he felt it must be tested by facts. As a contribution to the facts, by which the theory must be tested, he would refer to the structure of the highest Quadrumana as compared with man. Taking the brain of the gorilla, it presented more differences, as compared with the brain of man, than it did when compared with the brains oft he very lowest and most problematic form of the Quadrumana. The differences in cerebral structure between the gorilla and man were immense. The posterior lobes of the cerebrum in man presented parts which were wholly absent in the gorilla. The same remarkable differences of structure were seen in other parts of the body; yet he would especially refer to the structure of the great toe in man, which was constructed to enable him to assume the upright position; whilst in the lower monkeys it was impossible, from the structure of their feet, that they should do so. He concluded by urging on the physiologist the necessity of experiment. The chemist, when in doubt, decided his questions by experiments; and this was what is needed by the physiologist. Professor Huxley begged to be permitted to reply to Professor Owen. He denied altogether that the difference between the brain of the gorilla and  man was so great as represented by Professor Owen, and appealed to the published dissections of Tiedemann and others. From the study of the structure of the brain of the Quadrumana, he maintained that the difference between man and the highest monkey was not so great as between the highest and the lowest monkey. He maintained also, with regard to the limbs, that there was more difference between the toeless monkeys and the gorilla than between the latter and man. He believed that the great feature which distinguished man from the monkey was the gift of speech.
This subject was resumed another day by a paper "on the Intellectual Development of Europe, considered with Reference to the Views of Mr. Darwin and others, that the Progression of Organisms is determined by Law," by Professor Draper, M.D., of New York. The object of this paper was to show that the advancement of man in civilization does not occur accidentally or in a fortuitous manner, but is determined by immutable law. [... ]
 The announcement of this paper attracted an immense audience to the section, which met in the library of the New Museum. The discussion was commenced by the Rev. Mr. Cresswell, who denied that any parallel could be drawn between the intellectual progress of man and the physical development of the lower animals. So far from Professor Draper being correct with regard to the history of Greece, its masterpieces in literaturethe Iliad and the Odyssey were produced during its national infancy. The theory of intellectual development proposed was directly opposed to the known facts of the history of man. Sir B. Brodie stated he could not subscribe to the hypothesis of  Mr. Darwin. His primordial germ had not been demonstrated to have existed. Man had a power of self-consciousnessa principle differing from anything found in the material worldand he did not see how this could originate in lower organisms. This power of man was identical with the Divine Intelligence; and to suppose that this could originate with matter, involved the absurdity of supposing the source of Divine power dependent on the arrangement of matter. The Bishop of Oxford stated that the Darwinian theory, when tried by the principles of inductive science, broke down. The facts brought forward did not warrant the theory. The permanence of specific forms was a fact confirmed by all observation. The remains of animals, plants, and man, found in those earliest records of the human race, the Egyptian catacombs, all spoke of their identify with existing forms, and of the irresistible tendency of organized beings to assume an unalterable character. The line between man and the lower animals was distinct; there was no tendency on the part of the lower animals to become the self-conscious intelligent being, man; or in man to degenerate and lose the high characteristic of his mind and intelligence. All experiments had failed to show any tendency in one animal to assume the form of the other. In the great case of the pigeons, quoted by Mr. Darwin, he admitted that no sooner were these animals set free than they returned to their primitive type. Everywhere sterility attended hybridism, as was seen in the closely allied forms of the horse and the ass. Mr. Darwin's conclusions were an hypothesis, raised most unphilosophically to the dignity of a causal theory. He was glad to know that the greatest names in science were opposed to this theory, which he believed to be opposed to the interests of science and humanity. Professor Huxley defended Mr. Darwin's theory from the charge of its being merely an hypothesis. He said it was an explanation of phenomena in Natural History, as the undulating theory was of the phenomena of light. No one objected to that theory because an undulation of light had never been arrested and measured. Darwin's theory was an explanation of facts; and his book was full of new facts, all bearing on his theory. Without asserting that every part of the theory had been confirmed, he maintained that it was the best explanation of the origin of species which had yet been offered. With regard to the psychological distinction between man and animals, man himself was once a monada mere atom; and nobody could say at what moment in the history of his development he became consciously intelligent. The question was not so much one of a transmutation or transition of species, as of the production of forms which became permanent. Thus the short-legged sheep of America were not produced gradually, but originate in the birth of an original parent of the whole stock, which had been kept up by a rigid system of artificial selection.
Admiral Fitzroy regretted the publication of Mr. Darwin's book, and denied Professor Huxley's statement, that it was a logical arrangement of facts. [...]
 Dr. Hooker being called upon by the President to state his views of the botanical aspect of the question, observed that the Bishop of Oxford having asserted that all men of science were hostile to Mr. Darwin's hypothesis, whereas he himself was favourable to it, he could not presume to address the audience as a scientific authority. As, however, he had been asked for his opinion, he would briefly give it. In the first place, his lordship, in his eloquent address, had, as it appeared to him, completely misunderstood Mr. Darwin's hypothesis. His lordship intimated that this maintained the doctrine of the transmutation of existing species one into another, and had confounded this with that of the successive development of species by variation and natural selection. The first of these was so wholly opposed to the facts, reasonings, and results of Mr. Darwin's work, that he could not conceive how any one who had read it could make such a mistakethe whole book, indeed, being a protest against that doctrine. [...]
 At the Royal Institution, on Feb. 6, Professor Huxley (who at the Oxford meeting subsequently appeared as the champion of Mr. Darwin's theory) read a paper "On Species and Races, and their Origin." After some preliminary remarks, in the course of which the speaker expressed his obligation for the liberality with which Mr. Darwin had allowed him to have access to a large portion of the MSS. of his forthcoming work, the phenomena of species in general were consideredthe horse being taken as a familiar example. The distinctions between this and other closely allied species, such as the asses and zebras, were considered, and they were shown to be of two kinds, structural or morphological, and functional or physiological. Under the former head were ranged the callosities on the inner side of the fore and hind limbs of the horseits bushy tail, its peculiar larynx, its short ears, and broad hoofs: under the later head, the fact that the offspring of the horse with any of the allied species is a hybrid, incapable of propagation with another mule, was particularly mentioned. Leaving open the question whether the physiological distinction just mentioned is, or is not, a universal character of species, it is indubitable that it obtains between many species, and therefore has to be accounted for by any theory of their origin. The species Equus caballus, thus separated from all others, is the centre round which a number of other remarkable phenomena are grouped. It is intimately allied in structure with three other members of the existing creation, the hyrax, the tapir, and the rhinoceros; and less strait, though still definite bonds of union connect it with every living thing. Going back in time, the horse can be traced into the Pliocene formation, and perhaps it existed earlier still; but in the newer Miocene of Germany it is replaced by the hippotherium, an animal very like a true equus, but having the two rudimental toes in each foot developed, though small. Further back in time, in the Eocene rocks, neither equus nor hippotherium has been met with, nor rhinocerous, tapirus, or hyrax; but instead of them, a singular animal, the palæotherium, which exhibits certain points of resemblance with each of the four existing genera, is found. The speaker pointed out that these resemblances did not justify us in considering the palæotherium as a more generalized type, any more than the resemblance of a father to his four sons justifies us in considering him as a ore generalized type than theirs. The geographical distribution of  the equidæ was next considered, and the anomalies and difficulties it offers were pointed out; and lastly the variations which horses offer in their feral and their domesticated condition, were discussed. The questions thus shown to be connected with the species horse, are offered by all species whatever; and the next point of the discourse was the consideration of the general character of the problem of the origin of species of which they form a part, and the necessary conditions of its solution. So far as the logic of the matter goes, it was proved that this problem is of exactly the same character as multitudes of other physical problems, such as the origin of planets, or the origin of strata of marble; and a complete solution of it involved1. The experiment determination of the conditions under which bodies having the characters of species are producible; 2. The proof that such conditions are actually operative in nature. Any doctrine of the origin of species which satisfies these requirements must be regarded as a true theory of species; while any which does not is, so far, defective, and must be regarded only as a hypothesis whose value is greater or less according to its approximation to this standard.
It is Mr. Darwin's peculiar merit to have apprehended these logical necessities, and o have endeavoured to comply with them. The pigeons called pouters, tumblers, fantails, &c., which the audience had an opportunity of examining, are in his view the result of so many long-continued experiments on the manufacture of species; and he considers that causes essentially similar to those which have given rise to these birds are operative in nature now, and have in past times been the agents in producing all the species we know. If neither of these positions can be upset, Mr. Darwin's must be regarded as a true theory of species, as well based as any other physical theory; they require, therefore, the most careful and searching criticism. After pointing out the remarkable differences in structure and habit between the pouter, fantail, tumbler, and the wild Columba livia, the speaker expressed his entire agreement with Mr. Darwin's conclusion, that all the former domesticated breeds had arisen from the last-named wild stock; and on the following grounds1. That all interbreed freely with one another. 2. That none of the domesticated breeds presents the slightest approximation to any wild species but C. livia, whose characteristic markings are at times exhibited by all. 3. That the known habits of the Indian variety of the rock pigeon (C. intermedia) render its domestication easily intelligible. 4. That existing varieties connect the extremest modifications of the domestic breeds by insensible links with C. livia 5. That there is historical evidence of the divergence of existing breeds, e. g., the tumbler, from forms less unlike C. livia.
Mr. Huxley then analysed the process of evolution by which the domesticated breeds had been produced from the wild rock pigeon; and he showed its possibility to depend upon the two laws which hold good for all species, viz., 1. That every species tends to vary; 2. That variations are capable of hereditary transmission. The second law is well understood; but the speaker adverted to the miscomprehension which appears to prevail regarding the first, and showed that the variation of a species is by no means an adaptation to conditions in the sense in which that phrase is commonly used. Pigeon-fanciers, in fact, subject their pigeons to a complete uniformity of conditions; but while the similarly used feet, legs, skull, sacral vertebræ, tail feathers, oil gland, and crop undergo the most extraordinary modifications; on the other hand the wings, whose use is hardly ever permitted to the choice breeds, have hitherto shown no sign of diminution. Man has not as yet been able to determine a variation; he only favours those which arise spontaneously, i.e., are determined by unknown conditions. It must be admitted that, by selection, a species may be made to give rise experimentally to excessively different modifications; and the next question is, Do causes adequate to exert selection exist in nature? On this point, the speaker referred his audience to Mr. Darwin's chapter on the struggle for existence, as affording ample satisfactory proof that such adequate natural causes do exist. There can be no question that just as man cherishes the varieties he wishes to preserve, and destroys those he does not care about; so nature (even if we consider the physical world as a mere mechanism) must tend to cherish those varieties which are better fitted to work harmoniously with the conditions she offers, and to destroy the rest.
There seems to be no doubt, then, that modifications equivalent in extent to the four breeds of pigeons, might be developed from a species by natural causes; and therefore, if it can be shown that these breeds have all the characters which are ever found in species, Mr. Darwin's case would be complete. However, there is as yet no proof that, by selection, modifications having the physiological character of species (i.e., whose offspring are incapable of propagation inter se) have ever been produced from a common stock. No doubt the numerous indirect arguments brought forward by Mr. Darwin to weaken the force of this objection are of great weight; no doubt it cannot be proved that all species give rise to hybrids infertile inter se; no doubt (so far as the speaker's private conviction went), a well-conducted series of experiments very probably would yield us derivatives from a common stock, whose offspring should be infertile inter se; but we must deal with facts as they stand, and at present it must be admitted that Mr. Darwin's theory does not account for all the phenomena exhibited by species; and, so far, falls short of being a satisfactory theory. [...]
A discourse on this subject has been delivered at the Royal Institution, by Professor Huxley. He reminded his audience of what is meant by geological time, the forms of animal and vegetable life found in the lowest strata or layers of the earth's crust being considered to be the earliest created. He stated that it was the growing conviction of geologists that the remarkable changes in the earth's crust are not due to violent rapid action, as supposed by early observers, but rather to the efficacy of gentle forces operating through very long periods of time, as seen now in the slow-floating ice of glaciers and the slow-growing coral reefs. He also considered that palæontologists had already exaggerated the number of animals viewed as extinct. After long investigation he concluded that of 120 ordinal types of animals only eight or nine types were extinct; and he added, on the authority of Dr. Joseph Hooker, the eminent botanist, that of the 200 ordinal types of plants not one was wanting. Professor Huxley exemplified his views from all departments of the animal kingdomfrom the Polyzoa up to the Vertebrataspecimens of each being found in very low strata. He did not, therefore, believe that there was much greater difference between the earth's appearance in early geological times, and in our own, than there is now between the different regions of the globe. He remarked, in conclusion, that the little changes in the persistent types of animal and vegetable life appeared to him to "indicate that each is but the  result of an enormous series of antecedent changes of form, the whole of which are perhaps for ever hidden from us in the abyss of pre-geologic time."Illustrated London News.
C. Blinderman & D. Joyce