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The above will explain itself to those who are already familiar with the subject, but a few words may be added for others. If the species of animals and plants were created independently of all other species, then they must have been made as either perfect and fully formed individuals or as seeds and eggs. The former view is here ascribed to Milton rather than to Moses or Scripture, because most intelligent people now admit that the earlier chap

parallelism between the different stages of life in the individual and those in the entire group of the molluscous order Tetrabranchiata." (Mem. Boston Soc. Nat. Hist. Vol. I, part ii. 1867.) Prof. Hyatt remarks that Dr. Dawson has "given Prof. Cope the undivided credit of discovering the law of acceleration, whereas the memoir referred to above, which has escaped Dr. Dawson's notice, will remove all doubt that the aim of a large part of the observations there recorded, is identical with those of Prof. Cope's more elaborate essay. We have no desire for controversy but feel that silence in the present instance would place in a false light the object of these investigations, and vitiate the original value of the results of much labour not yet published." (Loc. cit. 234.)

We may add that Prof. Hyatt's paper was read Feb. 21, 1866, and Prof. Cope's on the Cyprinoid Fishes, in which his views were first enunciated, in Oct. 19 of the same year, though only published in the Trans. Amer. Philos. Soc., vol. 13, in 1869, after his elaborated views on the origin of species had appeared in the Proc. Phil. Acad. Sciences for 1868. No one who knows Prof. Cope can doubt that he, like Dr. Dawson and the author of the review here copied from The Nation, was unacquainted with the views of Prof. Hyatt. In justice to the latter, however, as an independent worker in this field, it is well to put these facts on record to avoid any future misconceptions.

It should perhaps be explained that Dr. Dawson's reasons for preferring the theory of Messrs. Hyatt and Cope did not imply any adhesion on his part to the hypothesis of derivation, but was based merely on the circumstance that the possibility of the passage of an animal from one genus to another by acceleration or retardation of development, seems to be proved by at least a few though perhaps exceptional facts, open to observation; while the change of one species into another is totally destitute of any observed examples or positive proof.-Eds. CANADIAN NATURALIST.

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ters of Genesis cannot reasonably be interpreted in their literal sense; so that for a distinct statement of this view we must look to the great English poet, who, however, was not a scientific man.* The idea that organisms were created as eggs, which have a simpler structure, is less difficult to comprehend than the foregoing, but it is not easy to see how this could occur with the higher animals whose young are born alive, and not in the form of eggs. A rather vague enunciation of this idea is contained in a little work by Swedenborg, which is probably to be regarded as purely philosophical and not as one of his theological works.

The second and more numerous family of theories is called "Derivative," because they all involve the supposition that in some way the lower and earlier forms have served as the means of producing higher and later ones. But it will be seen that they differ essentially as to the manner of this derivation. Lamarck was impressed with the amount of variation in size and form which the parts of an animal may undergo in consequence of their use or disuse, and so indirectly from any desire or appetency" which the animal experienced, e. g., a fish might thus become a quadruped if forced to live upon the land, and an ape might become a man. The amount of change in any one generation might be very slight, but the next generation would inherit, increase, and perpetuate the transformation.

In the endeavour to give a concise statement of Darwin's own theory, we suffer from an "embarras de richesses;" for not only is his own work one long presentation of it in many different aspects, but each later writer upon the subject has given his particular version, and from a different stand-point. Summary expressions of the theory are given by our author on pages 40, 70, 178, 412, 437; but a more diagrammatic enunciation is that of Wallace, who not only presented publicly an independent theory of natural selection at the same time with Darwin (1858), but has since paid a warm tribute to the latter's work, while expressing a doubt respecting the sufficiency of that theory for the production of man. With a few unimportant changes, his presenta

tion is as follows:

"Paradise Lost," Book VI.

"Worship and Love of God," Section 3.

"Contributions to the Theory of Natural Selection." London and New York: 1870. Pp. 302.

"1. Tendency of individuals to increase in number, while yet the actual number remains stationary.

"2. A struggle for existence among those which compete for food and endeavour to escape death.

"3. Survival of the fittest; meaning that those which die are least fitted to maintain their existence.

"4. Hereditary transmission of a general likeness.

“5. Individual differences among all.

"6. Change of external conditions universal and unceasing. "7. Changes of organic forms to keep them in harmony with the changed conditions: and as the changes of condition are permanent, in the sense of not reverting back to identical previous conditions, the changes of organic forms must be in the same sense permanent, and thus originate species."

The following passages from the "Origin of Species" may aid the comprehension of what the author admits to be a complex hypothesis:

"There is a struggle for existence leading to the preservation of profitable deviations of structure and insects"—(p. 412.) "Natural selection acts solely through the preservation of advantageous variation, and it acts with extreme slowness, at long intervals of time, and only on a few inhabitants of the same region" (p. 108.) "It is not probable that variability is an inherent and necessary contingent under all circumstances; variability is governed by many unknown laws (p. 50). "We are profoundly ignorant of the cause of each slight variation or individual difference (p. 192). "Nature gives successive variations; man adds them up in certain directions useful to him" (p. 40).

We italicise man because we are convinced that the grand fallacy in Darwin's theory lies just here, in the assumption that the selection and propagation of useful variations by man is in any way comparable to what takes place in nature. What is proved by all his works is this: that, so far as experience goes, no two created things are identical; that in many cases naturalists differ in their estimate of the value of the distinctions existing between individuals, so that what some call varieties others regard as species (a mighty question, which can only be decided by comparing great numbers of individuals of an undoubted species, and especially the progeny of a single pair); that by constant attention, by saving such as meet his wants and rejecting the

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rest, man has produced very strongly marked varieties, which continue" permanent so long as this care is given, but which, the instant it is relaxed and a free crossing with other breeds is allowed, show that they are only varieties and not true species by reverting to the original stock. It may also be admitted that in nature a somewhat similar selection takes place, especially under the form of "sexual selection," but there is as yet no evidence whatever that natural species can be compared to the breeds of domesticated animals; and to ascribe to "selection" of any kind the power of originating species merely because it can preserve useful individual varieties, is as illogical as-if so homely a simile is allowable to suppose that the man who is able to manage his own house is, therefore, competent to "keep a hotel." Natural selection may be a true cause, but it is not shown to be a sufficient

cause.

It may here be noted that reversion is not mentioned in any of the statements of the theory of natural selection by either Darwin or Wallace. Yet the former treats of the subject at length, and even depends upon its agency, after the lapse of thousands of years, to account for the sudden reappearance of otherwise inexplicable structures; so that, if we give to reversion the weight which Darwin himself allows it when it favours his views, his arguments against its action (pages 28 and 160) do not remove what is really a very serious objection to the theory of natural selection as applied to the production of specific forms in nature.

This whole subject is well presented by Mivart in the chapter on "Specific Stability;" and we have alluded to it here because it has always seemed to us to involve a fundamental fallacy which the author of "Natural Selection" is bound to remove.

The object of the "Genesis of Species" is "to maintain the position that natural selection acts, and, indeed, must act; but that still, in order that we may be able to account for the production of known kinds of animals and plants, it requires to be supplemented by the action of some other natural law or laws, as yet undiscovered" (page 5). This is, we may remark, but one of the numerous evidences that, while the general theory of "derivation" has been steadily gaining adherents even from among its original opponents, yet "natural selection"-Darwinism "pure and simple"-has been, and is still, losing ground even with those who were inclined to adopt it. Huxley "adopts it

only provisionally."* McCosht admits that "it contains much truth, but not all, and overlooks more than it perceives." Lesley‡ says, "All agree that it is true if kept within the regions of variety, but it is disputed whether it be true for actual specific differences." Wallace denies its sufficiency in the case of man, and Darwin himself has modified his views somewhat in this last edition of the "Origin of Species;" furthermore, he admits "the existence of difficulties so serious that he can hardly reflect on them without being staggered" (p. 167); and that "scarcely a single point is discussed on which facts cannot be adduced often apparently leading to conclusions opposite to mine" (p. 18). Indeed, with characteristic candour, he specifies certain ideas which if proved, would be fatal: "If it could be proved that any part of the structure of one species had been formed for the exclusive good of another species, it would annihilate my theory" (p. 196). We may, for example, yet learn the use which the "rattle" and the expanded hood have for the rattlesnake and the cobra, but Mivart is inclined to believe they are rather injurious, since they warn the prey (p. 50). Another such "fatal idea" is the doctrine that "many structures have been created for beauty in the eye of man or for mere variety" (p. 194). And here our author seems to contradict himself when, upon the same page, he admits that " Imany structures are now of no direct use to their possessors, and may never have been of any use to their progenitors"a subject which has been well discussed by the Duke of Argyll.§ The theory of natural selection implies that all changes are minute and gradual; and also that only useful structures are preserved and augmented. Prof. Mivart points out the difficulty of explaining the origin of the unsymmetrical form of the flounders, etc. (p. 37), of the limbs of animals which, in their earliest and minutest form, must have been mere buds or roughnesses, and thus rather impediments to the progress of our ancient aquatic progenitor (p. 39). Darwin further admits that "it is impossible to conceive by what steps the electric organs of fishes were produced (p. 184), also that the absence of imperfectly organized forms in the lowest strata of the earth's crust is inex

• "Man's Place in Nature," p. 128.

Report of recent lectures.

"Man's Origin and Destiny."

§ "Reign of Law," seventh edition, p. 230.

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