and in some of the Volvocineæ (Stephanosphæra, Eudorina).

Plainly then, the further one examines the facts, the more enlarged becomes the conception of degenerative evolution. It is not confined to unusual, abnormal or pathological cases. Degeneration is

not an accident in evolution: it is the obverse of progressive evolution and the necessary complement of every transformation whether anatomical or social.

Whatever transformation may be studied, it will be found that change is always accompanied by an elimination of some parts and that in the interests of the organism as a whole these useless parts gradually degenerate. When a whole organization begins to undergo retrogressive evolution and to decay, it is frequently in the interests of some still larger organization. Individuals or species out of harmony with their surroundings disappear to make room for others. August Comte has shown how death is a progressive agency in the social organization removing the worn-out tissues and leaving room for new and more plastic intelligences. All progress implies necessary eliminations. In the domain of society, those who are victims and who from birth, education, or interests, attach themselves to the decaying institutions naturally see only the degenerative side of the change; but those who regard the process as a whole and do not concentrate their attention upon the injured interests and

individual sufferings will see the other side of the movement.

When a social organism is degenerating there is considerable opposition to its complete disappearance, and so as Houzeau has said (see the summary of Book III.) it is to be expected that living and superior civilizations drag behind them a trail of débris from dead civilizations.

BOOK II

THE PATH OF DEGENERATIVE

EVOLUTION

PART I

THE SUPPOSED LAW THAT DEGENERATION RETRACES THE STEPS OF PROGRESS

It is a common opinion, supported partly by the etymology of the word, that retrogression is a tracing backwards of progression.

"In the degeneration of organizations fallen out of use," M. A. Lameere has said, "it is to be observed that the structures formed most recently and most specialized are the first to disappear, and that the most fundamental characters are those which persist longest: that in fact degenerative evolution retraces the steps made by progressive evolution. Peculiarities recently acquired, if they become disused, rapidly disappear, while dispositions of a more ancient kind have a persistence almost exactly proportioned to their age.1

This supposed biological law of retracement has 1A. Lameere, Esquisse de la Zoologie, Bruxelles, Rosez, p. 184.

penetrated to psychology and sociology. In 1868 Hughlings Jackson, in the study of certain maladies of the nervous system, had arrived at the conclusion that, "In the degeneration of this system the higher functions, those more complex, specialized and voluntary, disappear more quickly than the lower, simpler, less specialized and more automatic functions." 1

Starting from this point, and expressing it in terms of physiology, Ribot formulates as follows the law of degeneration of will and memory: "The dissolution of the will occurs in a retrograde fashion, from the more voluntary and complex to the less voluntary and simpler-that is to say, towards automatism." 2

So also in progressive loss of memory, the degeneration proceeds from the less stable to the more stable. "It begins with recent acquisitions not firmly rooted in the brain, rarely repeated, and so not firmly associated with others, in fact with the least organized parts of memory. It ends with sensory memory which is instinctive, and is deeply rooted in the organism, or is indeed a part of the organism itself." 3

These retrograde transformations of the nervous centres have their echoes in the modes in which ideas and feelings are expressed. Paul Heger, in

1 Ribot, Maladies de la Mémoire, p. 29. Dallemagne (Dégénérés et Déséquilibrés), p. 430.

2 Maladies de la Volonté, p. 150. Paris, F. Alcan.

3 Maladies de la Mémoire, p. 94.