that type of degeneracy which appears in spite of a satisfactory environment. The defect here is clearly germinal; it is, in fact, a germ-variation, and as such is transmissible to subsequent generations in accordance with the laws of heredity. In view of this important and far-reaching difference between these two types, usually comprehended by the word degeneracy,' some verbal distinction is clearly necessary. In my opinion that term should be restricted to the latter group, accordingly I venture to define degeneracy as 'a retrograde condition of the individual resulting from a pathological variation of the germcell'; and it is in this sense that it will here be used. Perhaps the most convenient word to denote the somatic modification arising from a defective environment would be 'decadency.' Degeneracy, then, is the expression of a germvariation. It is generally accepted by biologists that variations of the germ-cell tend to be transmitted to subsequent generations. It is doubtful whether this transmission is invariable, and the laws governing it are still very imperfectly known, but, as a broad fact, it is certainly true. It follows that the occurrence of variations is a phenomenon of the utmost importance to the future of the race. Such variations may be divided into two main groups. Firstly, those which connote an increased potentiality for development in some particular direction, thereby placing the individual at a greater advantage in the struggle for existence. These may be termed 'progressive' variations, and they obviously lie at the root of progressive racial evolution. Secondly, those which connote a diminished potentiality for development of such a nature as to impair the survival value. These may be termed 'retrogressive' variations and lie at the root of social degeneracy. It is with this latter class only that we are now concerned. The prevention of the perpetuation of these retrogressive variations is clearly a social problem of great moment, and comprises what is known as restrictive or negative eugenics. But the problem of their causation is even more important; for restrictive eugenics, however complete, can never prove entirely satisfactory so Vol. 228.--No. 452. D adolescence; also to the stunted growth and poor physique, often the actual disease and deformity, which follow insanitary surroundings, deprivation of suitable food and exercise, and general neglect or mismanagement, during the early months and years of development. These are conditions with which most of us are only too familiar; and probably no one would deny that under such adverse surroundings the individual must fail to attain that degree of development of which he is innately capable. On the other hand, we are equally familiar with instances in which, in spite of the most hygienic surroundings, the best education and the most careful upbringing, the individual never reaches the average developmental plane. Many children of this type die within a few months of birth, not so much from actual disease as simply because they have not strength to live. Others survive, but are physically, mentally or morally deficient. Doubtless in some cases there may be obscure faults in the environment, but there are very many in which this is not so, and in which there are clear indications of an innate defect of potentiality; in other words, of the fault being in the seed and not in the soil. The great bulk of the mentally deficient belongs to this group. The difference between these two types of so-called degeneracy, however, lies not only in their mode of causation, but in their ultimate results. That which is due to an inadequate or adverse environment acting upon the embryo, that is, after fertilisation of the germcell has taken place, is, in most instances, an affection of the cells of the body only. These are incapable of attaining their full development, because some of the necessary external stimuli to that development are lacking. If the want is supplied before the period of growth is past, the arrears may be made up; if not, some degree of permanent defect results. In some cases it is probable that the germ-plasm which is stored within the individual, to give rise, in due time, to another generation, may also be affected; but in most instances this is not so. What is produced is a somatic modification only, the germinal potentiality of the seed being unimpaired. The case is entirely different with regard to that type of degeneracy which appears in spite of a satisfactory environment. The defect here is clearly germinal; it is, in fact, a germ-variation, and as such is transmissible to subsequent generations in accordance with the laws of heredity. 6 In view of this important and far-reaching difference between these two types, usually comprehended by the word degeneracy,' some verbal distinction is clearly necessary. In my opinion that term should be restricted to the latter group, accordingly I venture to define degeneracy as 'a retrograde condition of the individual resulting from a pathological variation of the germcell'; and it is in this sense that it will here be used. Perhaps the most convenient word to denote the somatic modification arising from a defective environment would be 'decadency.' Degeneracy, then, is the expression of a germvariation. It is generally accepted by biologists that variations of the germ-cell tend to be transmitted to subsequent generations. It is doubtful whether this transmission is invariable, and the laws governing it are still very imperfectly known, but, as a broad fact, it is certainly true. It follows that the occurrence of variations is a phenomenon of the utmost importance to the future of the race. Such variations may be divided into two main groups. Firstly, those which connote an increased potentiality for development in some particular direction, thereby placing the individual at a greater advantage in the struggle for existence. These may be termed 'progressive' variations, and they obviously lie at the root of progressive racial evolution. Secondly, those which connote a diminished potentiality for development of such a nature as to impair the survival value. These may be termed 'retrogressive' variations and lie at the root of social degeneracy. It is with this latter class only that we are now concerned. The prevention of the perpetuation of these retrogressive variations is clearly a social problem of great moment, and comprises what is known as restrictive or negative eugenics. But the problem of their causation is even more important; for restrictive eugenics, however complete, can never prove entirely satisfactory so Vol. 228.-No. 452. D long as degenerates are still being produced de novo. Accordingly it is chiefly with the question of causation that it is proposed to deal. There are three chief views as to this causation, which may be discussed seriatim. The first is, that degeneracy is not the expression of any new germinal change, but the perpetuation of a defect which has existed in certain strains or stocks of the human race from the very beginning or from a Simian ancestry. This idea has probably occurred to most thinkers on the subject, but it has recently again been advanced by Dr C. B. Davenport of America. Dr Davenport, speaking of the origin of mental defect, says: 'The conclusion is forced upon us that the defects of this germ plasm have surely come all the way down from man's ape-like ancestors, through two hundred generations or more. The germ plasm that we are tracing remains relatively simple; it has never gained, or only temporarily, at most, the one or the many characteristics whose absence we call (quite inadequately) "defects." Feeble-mindedness is thus an uninterrupted transmission from our animal ancestry. It is not reversion; it is direct inheritance.' Now, with regard to this theory, we must either assume that the defect has been present since the very origin of life, or, that it has appeared at some subsequent period. On the former view it is presumed that the innate potentiality only sufficed for the attainment of a certain low stage of mental development; degeneracy, however, is no mere evolutionary arrest at some particular phase; it is usually seen as, if I may venture to use such a term, a progressive retrogression of certain stocks. If, however, we admit that the variation has made its appearance at some later stage of evolution, then this theory affords no explanation as to its causation; it simply pushes the enquiry back to that period, 'two hundred generations or more.' In this connexion it may be remarked that atavism is not uncommonly invoked as the explanation of feeblemindedness, which is one of the most prevalent forms of *The origin and control of mental defectiveness,' 1912. degeneracy. It is contended that, for some reason or other, these persons reproduce, or hark back to, a stage of mental development which was typical of savage or prehistoric man, but from which normal mankind have evolved. It is inferentially suggested that, although mental defectives are incapable of holding their own in a civilised community, they would not be incapable of so doing among these more primitive types. I cannot accept this view. I find it exceedingly difficult to believe that the feeble-minded members of a civilised community would be any better able to hold their own among a community of savages than they are in their present environment; and I find it still more difficult to imagine that such persons represent a normal developmental phase in the mental evolution of the human race. In this place also reference may be made to a recent work by V. A. Moschkoff ('Neue Theorie von der Abstammung des Menschen und seiner Degeneration'). This author looks upon the whole of mankind as being blended in various degrees from two types-white diluvial man and Pithecanthropus. He describes the physical, mental and moral characteristics of these types with a minuteness which puts the deductive ability of Owen completely in the shade, and which might, indeed, almost be the outcome of a personal acquaintance with these primeval beings in the flesh. White diluvial man would appear to have been a sort of Apollo, the possessor of many beauties and virtues, and of a body which was in every way more perfect than any now existing. Pithecanthropus, on the other hand, was a speechless, repulsive being, apparently somewhat midway between an African pygmy and a modern gorilla. According to Moschkoff, not only is degeneracy, as seen in idiots, cretins, and certain ethnic groups, due to a reversion to the pithecanthropic element, but the alternate expression of the characters of these two stocks takes place at different ages in the same individual and at different cycles in the life of the nation, and so leads to successive alterations of individual character, and even to progressive and retrogressive changes involving the whole community. Even civil wars and internal dissensions, which the sociologist usually attributes to economic causes, are claimed by the author as being due to the |