pation of motion; during which the matter passes from an indefinite, incoherent homogeneity to a definite, coherent heterogeneity; and during which the retained motion undergoes a parallel transformation" (p. 396).

This definition is an evolution out of a protracted series of arguments as presented in several consecutive chapters. In its successive stages, it assumed the following forms:-"We shall everywhere mean by evolution, the process which is always an integration of matter and a dissipation of motion" (p. 286); "Evolution is definable as a change from an incoherent homogeneity to a coherent heterogeneity" (p. 360); "Evolution is a change from an indefinite, incoherent homogeneity, to a definite, coherent heterogeneity, through continuous differentiations and integrations." This last mentioned form Professor Tait translates as follows: "Evolution is a change from a nohowish, untalkaboutable all-alikeness, to a somehowish and in-general-talkaboutable notall-alikeness, by continuous somethingelseifications and sticktogetherations."

Even Spencer's most elaborate definition finds itself the victim of the evolutional process, for on page 430, after supposing we had grasped the whole truth, we are startled by the announcement, "The continued changes which characterize evolution, in so far as they are constituted by the lapse of the less heterogeneous into the more heterogeneous, are necessary consequences of the persistence of force." Alas, the definition is not through its transformations and improvements; on page 458 we read, "A part-cause of evolution is the multiplication of effects; and this increases in geometrical progression as the heterogeneity becomes greater." Are the flukes of our anchor now fast in the crevices of unchangeable truth? No; "Evolution can end only in the establish

ment of the greatest perfection and the most complete happiness" (p. 517). "And thus there is suggested the conception of a past during which there have been successive evolutions analogous to that which is now going on; and a future during which successive other such evolutions may go on-ever the same in principle but never the same in concrete form” (p. 537). "The one

[spirit] no less than the other [matter] is to be regarded as but a sign of the Unknown Reality which underlies both."

Darwin, who may claim the honor of occupying a foremost rank among evolutionists, holds the generally accepted view of the descent of all the individuals of a species from a single birth-place and from one ancestral form, each species having subsequently established itself as widely as possible. He denies that species are an independent creation, and persists in regarding them as only varieties of a very early date; genera he looks upon as ancient species. The inherent predisposition in plants and animals to vary has sufficed, in conjunction with the causes originating in the intense struggle for existence, to modify all species and to produce the present diversity. All living organisms, he thinks, have been evolved from four or five primordial forms. "I believe," he says, "that all animals have descended from at most only four or five progenitors, and plants from an equal number." Again: "Possibly all the original beings which have ever lived on the earth are descended from some one primordial form into which life was first breathed." He does not regard variability as a necessary contingency of organic beings under all circumstances; he maintains that there are no species which refuse to vary provided they are placed under conditions 'avorable to the production of variations, and he affirms

that when once a species has begun to vary, its varieties are more and more subject to variation. He asks, "How could a savage possibly know, when he first trained an animal, whether it would vary in succeeding genera. tions?" Hence he infers that the animals which savages originally chose for domestication had no extraordinary inherent tendency to vary; varieties, he affirms, often vary more under domestication than distinct species in a wild state.

It may as well be frankly acknowledged that many and serious difficulties environ any hypothesis which we may choose to adopt. If we say that each new species, as it originated in some period subsequent to the dawn of life upon the earth, was an immediate creation of God, we seem to array ourselves against the Mosaic account; we certainly bring ourselves into conflict with the usually accepted interpretation. If we say that species, as they have successively appeared in geological eras, may have originated in spontaneous generation, we not only impose upon ourselves the task of proving that life can originate and actually has originated in certain combinations of inorganic matter, but we take a long stride towards materialism. If we say, new species have been evolved from pre-existing species, without the superintendence of an intelligent agent and without having been previously latent in parental forms, we accept evolution. If we say they are the natural unfoldings of forces originally communicated to the several species which were called into being by a direct fiat of the Divine Will, we accept a species of evolution and expose ourselves to renewed attacks from those who persist in affirming that if new species may originate in this manner, we ought not to assume that God did more originally than create one germ of life capable of

evolving all vegetable and animal organisms; indeed, that we ought to concede this. He may have imparted to oxygen, hydrogen, nitrogen, and carbon, when subjected to the influence of electricity, the power of originating protoplasm, or the physical basis of life.

We cannot insist too strongly that the question under discussion is not what is a possible or conceivable or probable way in which species originated, but what is the particular mode in which they actually originated. It is perhaps possible that the struggle for existence, which some evolutionists imagine they have forced upon the christian church, may yet evolve a second Bishop Butler; if this should prove to be the case much of the a priori reasoning of modern scientists would become, in his intellectual grasp, mere hay, wood, and stubble, in the burning of which new light would be thrown on Final Causes. The questions connected with the origin of new species, if ever settled, must be settled by induction, not by a priori arguments.

This new theory, now so vigorously advocated by an increasing number of those who are making the origin of species a special study, can scarcely be considered. a recent evolution from man's fertile brain. It was first propounded, though in crude form, by Aristotle in his Generation and Development of Animals. In 1759 Casper Friedrich Wolff, a careful observer and an acute reasoner, presented to the world his Theoria Generationis. The publication of this work in reality marks the birth of the theory of evolution. It made very few converts, however, during the life-time of its author, who received liberal installments of embittered prejudice and no small amount of ridicule. The work, however, produced results fifty years later. In 1809 Juan Lamarck presented the same views, in his Philosophic Zoolo

gique, in more captivating form, though his reasoning was less cogent and his array of facts more wearisome. He attempted to point out the steps by which nature in former times proceeded in her development of one class of beings from another, endeavoring to establish a graduated scale with the lowest organisms at one end and the human species at the other. He even essayed to prove that man's intellectual, moral, and religious faculties were the same in kind as those possessed by the brute creation-simply improvements. Fifty years later the world was presented with Darwinism, the popularity of which is in singular contrast with the reception given to the development hypothesis in preceding ages, and is, in the judgment of some, one of the marvels of this century. It is difficult to explain its rapid progress unless we concede that scientific studies were tending in this direction. The interesting style in which it is presented and the apparent fairness in the methods of reasoning have been efficient agencies, it is believed, in bringing about such extended results in a comparatively brief period of time.

Whilst evolutionists agree in asserting that new species have been evolved from pre-existing organisms, there is nevertheless great diversity of opinion as to the agency by which these changes have been effected. The following have been assigned:—

1. New specific forms have been regarded as the results of a "fortuitous concurrence of circumstances." This is only a wordy method of confessing an inability to explain the phenomena, and reminds one of the old dialecticians, who attempted to answer the question, "Has the ideal exemplar of species an existence independent of the individuals which constitute the species."

2. St. George Mivart believes that species possess an