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what is known as the special creation theory. Whether it is believed in the simple form just described, or whether creation is supposed to have taken place at widely separated points on the earth's surface, and in a manner less closely resembling the process by which the sculptor shapes his clay model, the process is essentially the same.

It is not really even an attempt at a scientific explanation of the facts of animal and vegetable existence, but is as evidently a mode of avoiding a real answer to a difficult question as is the explanation which savages give of disease, – that it is caused by the entrance into the body of an evil spirit.

But it has seemed probable, ever since geology became a science, that the beginnings of life on the earth were extremely simple, and of few genera and species. Says Professor Dana, than whom there is no higher American authority, —

“ The earliest representatives of animal life on the earth had no special organs, either of sense, of motion (excepting minute hairs or hair-like processes), or of nutrition, beyond, at the best, a mouth and a stomach. It iras life in its simplest or most elemental condition, systemless life; since neither of the four grand divisions of the animal kingdom was distinctly indicated. Such was the beginning." 1

1 Manual of Geology, p. 161.

In view of this, and of the further fact that it is only after the lapse of many millions of years, and the appearance and disappearance of innumerable legions of species, that we find any thing like the present number of forms of life to have existed on the globe, many scientists have been led to doubt that each species was the result of an act of creation, and have come rather to believe in some form of the development theory. According to this latter view (making no attempt to account for the origin of the earliest of all living things on the earth), it is supposed that the present species have been produced by descent, accompanied by changes of form, structure, and habits, from a few simple primitive forms. That is to say, the development theory, in view of all the known facts in regard to extinct and living species, concludes that the latter have been formed, and are now being formed, in a natural rather than in a supernatural manner, by the continued action upon the organisms of forces within and about them. How well this theory stands the great test of all theories, namely, being confronted with facts, it is the object of this little book to show. For twenty years before the appearance of his great work, “ The Origin of Species,” Mr. Darwin was engaged in collecting and classifying facts in regard to the occurrence of new varieties and species. Some such facts I will endeavor to state briefly in the following chapter.

i See The Life and Letters of Charles Darwin, Am. ed., vol. i., pp. 67-71, and chapters X. to XIII.

CHAPTER II.

CASES OF ORIGINATION OF VARIETIES AND

SPECIES.

ONE

NE of the first questions that would natu

rally occur to any one beginning to think out the problem of the origin of species would be, “ Has the time or the manner of beginning of any new species ever been discovered?" How this question is to be answered will depend entirely on what meaning is given to the word “species.”

If by it we understand a kind of animal or plant which cannot be shown to vary enough to become the same with any other kind, or to have been changed from any other; which in short is, and from the moment of its origin always has been, perfectly distinct from the nearest similar forms, - then, of course, it would be difficult to answer yes.

Such a definition of species would beg the whole question under discussion; that is, it would assume all that the advocates of the special creation theory wish to prove. But if any forms which differ from one another by an amount fairly equal to what, by the general consent of naturalists, usually separates species, may, whatever their variability or their origin, be counted as species, then it is easy to answer yes to the question asked at the beginning of this chapter. Yet, in studying cases in which such changes occur as may finally result in the production of new species, it must be remembered that the process of species-making will necessarily often be a slow one.

If the human race, the lower animals, and the plants of ancient Egypt, were much the same that they are today, it would be foolish to expect frequently to find great changes, in any race of living beings, coming about under our very eyes. At least, no such sudden change can often happen where all the conditions of life have remained as uniform as they have since the dawn of civilization in Egypt.

More than this, since we find, from the evidence of geology, that poplars existed hundreds of thousands of years ago, pines even millions, and that a genus of shell-fish (the Lingulella), almost or quite the same with a genus of the present day, has lasted for probably tens of

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