of which are continually being discovered, prove that he lived with a fauna which has now passed away, and under conditions of climate different from those which now obtain in the localityfacts confirmed by the mammalian remains which are sometimes found in true association with human handiwork in the Pleistocene gravels.

I have incidentally referred to the theory of pre-crag man. The evidence for the existence of such is based solely on roughlybroken flints which carry with them no conviction in the eyes of many. To admit that man existed in Pliocene times is to date him back far across the dial-plate of geological time, and only the student of geology can realise how much that means. In leaving this part of my subject I should mention that several leading archæologists have now come to the conclusion that the gap which was long supposed to separate the Older Stone Age from the newer did not exist, but that each melted into the other, and that human progress has not been seriously interrupted since man first began to chip flint. Flints found in the surface soil, which a short time back were unhesitatingly called Neolithic and said to date from a period only just anterior to the Age of Bronze in Britain, are now considered to be similar to forms found abroad and ascribed to the late Paleolithic Age. The abolition of the hiatus between the Older and Newer Ages of stone seems to do away with the necessity for some of the great physical changes for which long time was demanded, and its tendency is to shorten the periods in question and to bring Paleolithic man nearer to us. So the theory proves a corrective to the views of those who take us back far into the mists of geologic time.

I have next to speak of some of the theories concerning the descent of man, and to refer to the few skeletal remains of him which are known, and which can be safely placed in the Paleolithic Age. The theories, which I will attempt to summarize very briefly, are all based upon the doctrine of the evolution of man from the ape. Professor Sollas, writing in 1910, refers to the fact that Darwin omitted all reference to man because the question was beset with prejudice, but now he says Evolution has become an orthodox dogma, respectable beyond reproach. Our cousinship with the apes, more or less remote, is acknowledged without shame on our part, and let us hope without reason for shame on theirs. I need not trouble you with any theory of the earlier stages of the development of the manlike apes from a more primitive ancestry. The mazes of speculation on this head are

great and diverse, especially among our foreign friends. After stating some of these views, Sollas wisely says: "The crowd of primitive ancestors which are beginning to inhabit the world of thought are logical abstractions which may never have enjoyed any real existence in the flesh." He also points out that the phenomenon of regression has not been sufficiently considered in forming these hypotheses. Our study of extinct forms of life has taught us, especially among the invertebrates, that some species will reach a certain stage of development, like the Ammonites, and then return to the more simple forms of their ancestors and finally disappear. The skull of the Neanderthal man, with its high superciliary ridges and its retreating ape-like forehead, was long regarded as a missing link, and a creature from which we are descended. Now it is universally accepted that Neanderthal man was only one of the lines of divergence from the apes--a line which died out, and is not admitted to have a place in man's genealogical tree. Professor Carveth Read tells us all the promin ent characters that distinguish man from the anthropoids are the result of his having shown a special likeness for animal food; and he proceeds to show that this brought about life on the ground beyond the limits of the forest, the erect gait, the lengthening of the legs and specialization of the feet, the shortening of the arms and development of the hands, with other structural changes.

Another writer, Dr. Robinson, lays great weight on the development of the chin, not merely for its æsthetic value, but because of its relation to the faculty of articulate speech which differentiates man from the anthropoids. Concerning this, Dr. Elliot Smith considers that the development of the lower jaw had nɔ relation to speech, but that this faculty was brought about entirely by the development of the brain, so that when man had anything to say he had the equipment for saying it.

This development of the brain, Dr. Elliot Smith considersand there is no higher authority than he-was the determining factor in man's specialization. He does not look upon the Orang, the Chimpanzee and the Gorilla as ancestral forms of man, but as the more unenterprising members of man's family, who were not able to maintain the high level of cerebral development, but saved themselves from extinction by the acquisition of greater strength and a certain degree of specialization of structure. The assumption of the erect attitude and the faculty of speech, of which some make so much, was subordinate to the growth of the brain;

and in a long and powerful argument, which only an anatomist can really appreciate, it is shown how the development of those areas of the brain connected with tactile, visual, and acoustic impressions, and the storing of them in the chambers of memory, brought about the human brain, and all those changes in man's form which have differentiated him from some of the primates from which he has sprung.

Professor Sollas, who is a believer in the assumption of the erect attitude as the prime factor in man's differentiation, concludes the address from which I have already quoted, in these words: "How little we really know concerning the true course of human evolution is impressed upon us by the paucity of the evidence which we are able to adduce directly bearing on such speculations as we have considered." He then gives a quotation which, although the words of Huxley, are worthy of a divine: "Man alone possesses the marvellous endowment of intelligible and rational speech, whereby he has slowly accumulated and organized the experience which is almost wholly lost with the cessation of life in other animals, so that now he stands raised upon it as on a mountain-top, far above the level of his humbler fellows, and transfigured from his grosser nature by reflecting here and there a ray from the infinite source of truth."

In dealing with the few skeletal remains of man which we are sure belong to a period anterior to the Neolithic Age, we are in the more sober region of facts. Sir John Evans recognised only two divisions of the Paleolithic period-the river drift and cave periods. Led by French investigators, six are now widely recognized, which in the sequence of their age are the Chellean, Acheulean, Mousterian, Aurignacian, Solutrian, and Magdalenian. The evidence of the sequence of these periods rests largely upon the character of the implements which are assigned to them. All English archæologists do not, however, at present accept these divisions, because in English gravel beds the various forms of implements are so often found mixed together, that no stratification is possible. Human remains have long been known from the Magdalenian period. They give evidence of the existence of two contemporary races. The Cro-Magnon race, a tall people of a Mongolian type, and a race of short people like the modern Eskimo. It is an extraordinary fact that both races were of great cranial capacity, and endowed with larger brains than the average of any existing civilized people. In the Solutrian Age a race of men existed whose remains have been discovered on

Mentone, who did rude carving and mural paintings. The skulls are said to resemble those of the Bushman or Hottentot, but here again the cranial capacity is larger than that of any existing Negro race. Coming to the next older stage, the Mousterian, we are in possession of more numerous remains, and to it the Neanderthal skull belongs. From this material we learn that Mousterian man was short in stature, with a disproportionally large head and a face strangely unlike that of any human race with which we are familiar. A retreating forehead rises out of a bold depression above the massive eye-brow ridges. The orbits are large and round, and the massive lower jaw without a chin. In spite of the ape-like form of the head, the cranial capacity is not small, but even larger than that of the Australian aboriginal, who approaches most nearly to Neanderthal man in form. Neanderthal man is now, however, relegated to the back-water of the stream of human progression, and regarded, as I have said, as an instance of regression. Mousterian man is credited with having reached a certain stage in the evolution of religious ideas. The remains found had evidently been interred in a kind of tomb; weapons were buried with them, and in one case the leg of a bison placed beside, to provide food for the departed spirit.

Up to quite a recent period Mousterian man was the oldest known. The Heidelberg jaw, however, discovered in 1909, in association with remains of Elephas antiquus, is said to date back to the oldest, or Chellean period. The dentition of this jaw is human. The canine does not appear to have projected beyond the general level. More simian characters may be observed in the dentition of existing wild races, but the jaw itself offers a striking contrast to the dentition. It is massive, and the chin is entirely absent, the profile retreating in gentle curves as in the chimpanzee or gorilla. The genio-glossal spines are entirely absent in the apes. With the muscle of the same name these structures are connected with the power of speech, but their absence does not prove the inability to talk, as the jaw of the Bushman does not possess them. No remains of the skull were found, but from the fact that the Mousterian skull, though possessing simian characters, lodged a large human brain, it is fair to assume that such was the case with the Heidelberg man.

I speak lastly of the famous Piltdown skull, discovered in 1912, a relic of ancient man which has stirred the scientific world more, and aroused fiercer controversy, than any previous discovery of the same kind. The gravel in which the remains were found

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contained flint implements of the Chellean period, and fossilized remains of the mastodon, hippopotamus, and other Pleistocene animals, all mineralized in the same way as the broken pieces of the cranium and portion of the lower jaw of a human being, which were recovered from the same deposit. All authorities agree, these are the oldest human remains which have yet come to light. In our scientific publications are technical and full descriptions of these Piltdown remains, and from the fragments obtained, Dr. Smith Woodward has made a complete restoration of the skull and jaws. Summarized briefly, the result is to give us a jaw remarkably like that of the ape, with a brain of lower cerebral capacity than that of other Paleolithic men, and with certain characteristics of a simian nature. There are, however, not the projecting brow ridges of the Neanderthal man, and the general shape of the brain-case resembles that of the young chimpanzee. Two of the molars are in place, and by the shape of what remains in the frontal portion of the ramus, it was evident that space was left for large canine teeth of ape-like character. So the restoration included large interlocking canines. This restoration was, however, called in question by Dr. Keith, of the Royal College of Surgeons, who made another model with a human jaw and a brain capacity fully that of modern individuals. This criticism led Dr. Woodward to make a fresh restoration of the brain-case, which he has submitted to Dr. Elliot Smith, the result being to give a brain capacity within the range of the smallest human brains of the present day. The restoration of the jaw was confirmed by the fortunate discovery in August 1913, after a re-examination of the gravel, of the actual canine tooth which was missing. It is abnormally large, and by the way it is worn, must have been interlocking. Piltdown man, therefore, was a creature with a jaw resembling that of an ape, yet with the brain of a man, although bearing some simian affinities even in this respect. But on the question of the brain, the last word has not yet been said.

The conclusion of the whole is, that man's existence has not yet been proved beyond the period known as the Pleistocene; that the earliest known man had certain skeletal characteristics, which seem to connect him with the apes; that no fossil primate is known earlier than Eocene times, and between that and the Pleistocene period no remains have been found of any creature to which the familiar expression "missing link" may be applied; and lastly that in all our discoveries, the brain, on which so much