equivalent, and each retains all the functions of life (Spirogyra, Choanoflagellates, Hydra). The colony may disintegrate, but the cells or individuals set at liberty are capable of living alone, and do not form a society.1

As the organisation of a colony becomes more complicated, the units proceed to differentiate. Each one assumes certain functions in particular, and becomes less adapted to discharge others. If such a colony is dispersed, the individuals are incapable of maintaining a separate existence.2

1 (a) A thread of Spirogyra consists of cells placed end to end, physiologically connected with one another. Under certain conditions, however, quite apart from the phenomenon of cellular reproduction, all these cells are capable of isolating themselves. The colony is thus transformed into a set of individuals capable of maintaining a separate existence, and no longer in connection with one another.

(b) Among the Choanoflagellates, some consist of free individuals, while in others all the individuals are united by a common stalk, and intercommunicate by protoplasmic threads in the stalk. When, for some cause, these individuals separate, they never form themselves into a society.

(c) A colony of Hydra is formed by the budding of a single individual. While nourishment is abundant, all the individuals of the colony retain their connection with each other, and may themselves give rise to buds. On the other hand, when food is scarce, the colony disintegrates and each individual lives a free life without entering into social relations with its neighbours.

2 In some cases the terms individual and colony become extremely involved. Although one accept our view, it is difficult to rigorously apply our generalizations to such facts as the following: Certain male cephalopods, at the period of reproduction, separate from their bodies a specialized tentacle (hectocotyle) in which is stored the seminal fluid. This organ, set at liberty, swims in the

III. Communities and societies.-The bond existing between all the constituent parts of a society is not of the same nature as that which unites the members of a colony or the cells of an animal or plant. These physiological bonds are not comparsea, and after living there a certain time, enters the female cephalopod, to effect impregnation.

The individuality of this hectocotyle appears so obvious that for a long time it was regarded as a distinct species - some kind of worm. At first sight, then, the hectocotyle seems to be an individual. This, however, is not the case, as it reproduces, not a hectocotyle but a cephalopod.

Many Echinoderms, by a spontaneous act of protection, can separate their arms from their bodies. Such a separated arm may live, feed and slowly build up again a whole Echinoderm. Plainly, it would be impossible to indicate the precise point at which such an organ should be regarded as an individual. The vegetable kingdom abounds in analogous facts. A strawberry plant, for instance, gives off runners in the course of the Summer, which take root, and themselves become strawberry plants. So long as these young plants are insufficiently developed to maintain themselves, the mother-plant continues to supply them with nourishment. As soon, however, as the young shoot can dispense with this support, the runner atrophies, and the little plant begins a separate existence. By prematurely cutting the runner, the new plant may be compelled to live alone sooner than it naturally would have done.

With some other plants (Phalangium viviparum) the young shoots frequently retain their connection with the mother-plant, although quite capable of maintaining themselves. Under these circumstances it is obviously impossible to say if these plants represent colonies or free individuals. Speaking generally, it may be said that no precise line can be drawn between colonies and individuals. Many writers on the subject, and Perrier among the number, consider that every colony where there is a physical continuity among the members, should be regarded as an individual.

able, without forcing the analogy, although they have been so compared by some sociologists, to such means of communication between individuals and societies as exchange, traffic, roads, railways, telegrams and telephones. It is merely a matter of definition, and if societies are to be termed organisms, they should be distinguished as organisms by social contract, organismes contractuels (Fouillée).

This definition, however, only applies to those societies which owe their existence to a formal contract with definite objects in view, and not to ready-made communities consisting of individuals already united together without any preliminary contract. The latter is the case, for instance, in societies of ants or bees, and in human societies in those social groups in which the individuals are united by the bonds of consanguinity. The characters of such communities partly approach the characters of organic associations, but precisely as such natural communities approach societies by social contract, the differences between social groups and actual organisms become more marked. In the more complex forms of societies the results of the characters we have distinguished become most accentuated.

IV. Distinctive characters of societies of which the members are united by social contract.—(1) A cell cannot be part of two organisms or of two

organs at the same time.' On the other hand, there is no reason why the members of one social community should not belong to other communities at the same time.

2. Speaking generally, the biological conception of an organism denotes a definite thing—a plant or an animal in itself, quite distinct from similar organisms. In sociology, however, there is no precise line between co-existing social communities. Are we to regard, for instance, the families, communes and cantons of a state as distinct organisms, or merely as organs? Does a free town such as Hamburg or Frankfort cease to be an organism when it loses its independence? Take the various Swiss cantons, which are now mere organs of the Helvetic Confederation, like the Provinces of Belgium, or the Departments of France, would they become organisms on the rupture of the Federal bond? On the other hand, with the growth of international treaties between the states of Eastern Europe, will their social individuality disappear, and will they come to be regarded as are the United States of America, as the organs of an an organism in process of formation? These few examples suffice to show

1 When two organs are united into one whole, the cell exercises two totally different functions. The liver, as we now know, is a double organ consisting of a bile-forming liver, and the glycogenproducing liver, two organs which are embryologically distinct. The cells of which the liver is composed are both bile-secreting and glycogen-forming organs.

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that, so far as social matters are concerned, the conception of organisms is a pure convention. In the course of this treatise, we may therefore regard families, societies and nations as distinct organisms, or, with regard to their connection with other and vaster organizations, as organs of the latter.

3. The structure of an animal or plant depends upon the physical arrangements of its parts, and on the physiological links between those parts. The structure of a society depends upon the links of social contract existing among its members. We regard these as two very different things, and we cannot follow Tarde in pressing the analogy between them in the following way: "The length, breadth, and height of an organism are never very much out of proportion. With snakes and poplars the height or length preponderates; among flat fish the thickness is very small compared to the other dimensions, but in each instance the disproportion exhibited in extreme cases is not comparable to that shown by any social aggregate-such as China for instance, which is 3000 kilometres in length and breadth, and only one or two yards in average height, for the Chinese being a short race, build their edifices correspondingly low."

4. Organic modifications are effected more slowly and with greater difficulty than are social modifica

1 Les Monades et la Science sociale. (Tarde. Revue de Sociologie, 1893, p. 169.)