this subject, I would again respectfully urge that they must grapple with the whole of the facts, not one or two of them only. It will be admitted that, on the theory of evolution and natural selection, a wide range of facts with regard to colour in nature have been co-ordinated and explained. Until at least an equally wide range of facts can be shown to be in harmony with any other theory, we can hardly be expected to abandon that which has already done such good service, and which has led to the discovery of so many interesting and unexpected harmonies among the most common (but hitherto most neglected and least understood) of the phenomena presented by organised beings.

VII

CREATION BY LAW1

AMONG the various criticisms that have appeared on Mr. Darwin's celebrated Origin of Species, there is, perhaps, none that will appeal to so large a number of well educated and intelligent persons as that contained in the Duke of Argyll's Reign of Law. The noble author represents the feelings and expresses the ideas of that large class of persons who take a keen interest in the progress of science in general, and especially that of Natural History, but have never themselves studied nature in detail, or acquired that personal knowledge of the structure of closely allied forms, the wonderful gradations from species to species and from group to group, and the infinite variety of the phenomena of "variation" in organic beings, which is absolutely necessary for a full appreciation of the facts and reasonings contained in Mr. Darwin's great work.

Nearly half of the Duke's book is devoted to an exposition of his idea of "Creation by Law," and he expresses so clearly what are his difficulties and objections as regards the theory of "Natural Selection," that I think it advisable that they should be fairly answered, and that his own views should be shown to lead to conclusions as hard to accept as any which he imputes to Mr. Darwin.

The point on which the Duke of Argyll lays most stress is, that proofs of Mind everywhere meet us in Nature, and are more especially manifest wherever we find " contrivance or "beauty.' He maintains that this indicates the constant

1 First published in the Quarterly Journal of Science, October 1868; reprinted in Contributions, etc., with a few alterations and additions.

supervision and direct interference of the Creator, and cannot possibly be explained by the unassisted action of any combination of laws. Now, Mr. Darwin's work has for its main object to show that all the phenomena of living things, -all their wonderful organs and complicated structures, their infinite variety of form, size, and colour, their intricate and involved relations to each other, may have been produced by the action of a few general laws of the simplest kind, laws which are in most cases mere statements of admitted facts. The chief of these laws or facts are the following:

1. The Law of Multiplication in Geometrical Progression.All organised beings have enormous powers of multiplication. Even man, who increases slower than all other animals, could under the most favourable circumstances double his numbers every fifteen years, or a hundredfold in a century. Many animals and plants could increase their numbers from ten to a thousandfold every year.

2. The Law of Limited Populations.-The number of living individuals of each species in any country, or in the whole globe, is practically stationary; whence it follows that the whole of this enormous increase must die off almost as fast as produced, except only those individuals for whom room is made by the death of parents. As a simple but striking example, take an oak forest. Every oak will drop annually many thousands of acorns, but till an old tree falls not one of the millions of acorns produced can grow up into an oak. They must die at various stages of growth.

3. The Law of Heredity, or Likeness of Offspring to their Parents. This is a universal, but not an absolute law. All creatures resemble their parents in a high degree, and in the majority of cases very accurately; so that even individual peculiarities, of whatever kind, in the parents, are almost always transmitted to some of the offspring.

4. The Law of Variation.-This is fully expressed by the lines ::

"No being on this earthly ball,

Is like another, all in all."

Offspring resemble their parents very much, but not wholly -each being possesses its individuality. This "variation" itself varies in amount, but it is always present, not only in

the whole organism, but in every part of each organism. Every organ, every character, every feeling, is individual; that is to say, varies from the same organ, character, or feeling in every other individual.

5. The Law of unceasing Change of Physical Conditions upon the Surface of the Earth.-Geology shows us that this change has always gone on in times past, and we also know that it is now everywhere going on.

6. The Equilibrium or Harmony of Nature.-When a species is well adapted to the conditions which environ it, it flourishes; when imperfectly adapted it decays; when ill-adapted it becomes extinct. If all the conditions which determine an . organism's wellbeing are taken into consideration, this statement can hardly be disputed.

This series of facts or laws are mere statements of what is the condition of nature. They are facts or inferences which are generally known, generally admitted-but, in discussing the subject of the "Origin of Species," as generally forgotten. It is from these universally admitted facts that the origin of all the varied forms of nature may be deduced by a logical chain of reasoning, which, however, is at every step verified and shown to be in strict accord with facts; and, at the same time, many curious phenomena which can by no other means be understood are explained and accounted for. It is probable that these primary facts or laws are but results of the very nature of life, and of the essential properties of organised and unorganised matter. Mr. Herbert Spencer, in his First Principles and his Biology, has, I think, made us able to understand how this may be; but at present we may accept these simple laws without going further back, and the question then is-whether the variety, the harmony, the contrivance, and the beauty we perceive in organic beings can have been produced by the action of these laws alone, or whether we are required to believe in the incessant interference and direct action of the mind and will of the Creator. It is simply a question of how the Creator has worked. The Duke (and I quote him as having well expressed the views of the more intelligent of Mr. Darwin's opponents) maintains that He has personally applied general laws to produce effects

which those laws are not in themselves capable of producing; that the universe alone, with all its laws intact, would be a sort of chaos, without variety, without harmony, without design, without beauty; that there is not (and therefore we may presume that there could not be) any self-developing power in the universe. I believe, on the contrary, that the universe is so constituted as to be self-regulating; that as long as it contains Life, the forms under which that life is manifested have an inherent power of adjustment to each other and to surrounding nature; and that this adjustment necessarily leads to the greatest amount of variety and beauty and enjoyment, because it does depend on general laws, and not on a continual supervision and rearrangement of details. As a matter of feeling and religion, I hold this to be a far higher conception of the Creator and of the Universe than that which may be called the "continual interference" hypothesis; but it is not a question to be decided by our feelings or convictions-it is a question of facts and of reason. Could the change which geology shows us has continually taken place in the forms of life, have been produced by general laws, or does it imperatively require the incessant supervision of a creative mind? This is the question for us to consider, and our opponents have the difficult task of proving a negative, if we show that there are both facts and analogies in our favour.1

Mr. Darwin's Metaphors liable to Misconception

. Mr. Darwin has laid himself open to much misconception, and has given to his opponents a powerful weapon against himself, by his continual use of metaphor in describing the wonderful co-adaptations of organic beings.

"It is curious," says the Duke of Argyll, "to observe the language which this most advanced disciple of pure naturalism instinctively uses, when he has to describe the complicated structure of this curious order of plants (the Orchids). 'Caution in ascribing intentions to nature' does not seem to

1 In addition to the laws referred to above, there are of course the fundamental laws and properties of organised matter and the mysterious powers of Life, which we shall probably never be able to explain, but which must be taken as the basis of all attempts to account for the details of form and structure in organised beings.