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he is merely "tempted to believe in such simple relations as variation of climate and food, or introduction of enemies, or the increased number of other species, as the cause of the succession of races." But finally (Ist edit.) he ends the chapter by comparing the extinction of a species to the exhaustion and disappearance of varieties of fruit-trees : as if he thought that a mysterious term of life was impressed on each species at its creation.

The difference of treatment of the Galapagos problem is of some interest. In the earlier book, the American type of the productions of the islands is noticed, as is the fact that the different islands possess forms specially their own, but the importance of the whole problem is not so strongly put forward. Thus, in the first edition, he merely says :

“This similarity of type between distant islands and continents, while the species are distinct, has scarcely been sufficiently noticed. The circumstance would be explained, according to the views of some authors, by saying that the creative power had acted according to the same law over a wide area."-(1st edit. p. 474.)

This passage is not given in the second edition, and the generalisations on geographical distribution are much wider and fuller. Thus he asks :

"Why were their aboriginal inhabitants, associated ... in different proportions both in kind and number from those on the Continent, and therefore acting on each other in a different manner-why were they created on American types of organisation?"-(2nd edit. p. 393.)

The same difference of treatment is shown elsewhere in this chapter. Thus the gradation in the form of beak presented by the thirteen allied species of finch is described in the first edition (p. 461) without comment. Whereas in the second edition (p. 380) he concludes :

"One might really fancy that from an original paucity of birds in this Archipelago, one species has been taken and modified for different ends."

On the whole it seems to me remarkable that the difference

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between the two editions is not greater; it is another proof of the author's caution and self-restraint in the treatment of his theory. After reading the second edition of the 'Journal,' we find with a strong sense of surprise how far developed were his views in 1837. We are enabled to form an opinion on this point from the note-books in which he wrote down detached thoughts and queries. I shall quote from the first note-book, completed between July 1837 and February 1838: and this is the more worth doing, as it gives us an insight into the condition of his thoughts before the reading of Malthus, The notes are written in his most hurried style, so many words being omitted, that it is often difficult to arrive at the meaning. With a few exceptions (indicated by square brackets) * I have printed the extracts as written; the punctuation, however, has been altered, and a few obvious slips corrected where it seemed necessary.

The extracts are not printed in order, but are roughly classified.

“ Propagation explains why modern animals same type as extinct, which is law, almost proved."

“We can see why structure is common in certain countries when we can hardly believe necessary, but if it was necessary to one forefather, the result would be as it is. Hence ante. lopes at Cape of Good Hope; marsupials at Australia.”

“Countries longest separated greatest differences--if separated from immersage, possibly two distinct types, but each having its representatives—as in Australia.”

“Will this apply to whole organic kingdom when our planet first cooled?"

The two following extracts show that he applied the theory

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* In the extracts from the note-book ordinary brackets represent my father's parentheses.

7 On the first page of the note-book, is written “ Zoonomia "; this seems to refer to the first few pages in which reproduction by genimation is discussed, and where the “Zoonomia” is mentioned. Many pages have been cut out of the note-book, probably for use in writing the Sketch of 1844, and these would have no doubt contained the most interesting extracts,

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of evolution to the "whole organic kingdom" from plants to man.

“ If we choose to let conjecture run wild, then animals, our fellow brethren in pain, disease, death, suffering and famine-our slaves in the most laborious works, our companions in our amusements—they may partake (of ?) our origin in one common ancestor--we may be all melted together.”

“The different intellects of man and animals not so great as between living things without thought (plants), and living things with thought (animals).”

The following extracts are again concerned with an à priori view of the probability of the origin of species by descent [“ propagation," he called it).

The tree of life should perhaps be called the coral of life, base of branches dead; so that passages cannot be seen."

“There never may have been grade between pig and tapir, yet from some common progenitor. Now if the intermediate ranks had produced infinite species, probably the series would have been more perfect."

At another place, speaking of intermediate forms he says :

Cuvier objects to propagation of species by saying, why have not some intermediate forms been discovered between Palæotherium, Megalonyx, Mastodon, and the species now living? Now according to my view (in S. America) parent of all Armadilloes might be brother to Megatherium-uncle now dead."

Speaking elsewhere of intermediate forms, he remarks :

"Opponents will say-show them me. I will answer yes, if ou will show me every step between bulldog and gre hound."

Here we see that the case of domestic animals was already present in his mind as bearing on the production of natural species. The disappearance of intermediate forms naturally leads up to the subject of extinction, with which the next extract begins.

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"It is a wonderful fact, horse, elephant, and mastodon, dying out about same time in such different quarters.

"Will Mr. Lyell say that some [same?] circumstance killed it over a tract from Spain to South America ? (Never).

“They die, without they change, like golden pippins; it is a generation of species like generation of individuals.

“Why does individual die? To perpetuate certain peculiarities (therefore adaptation), and obliterate accidental varieties, and to accommodate itself to change (for, of course, change, even in varieties, is accommodation). Now this argument applies to species.

"If individual cannot propagate he has no issue--so with species.

If species generate other species, their race is not utterly cut off :-like golden pippins, if produced by seed, go onotherwise all die.

“ The fossil horse generated, in South Africa, zebra-and continued-perished in America,

“ All animals of same species are bound together just like buds of plants, which die at one time, though produced either sooner or later. Prove animals like plants-trace gradation between associated and non-associated animals—and the story will be complete."

Here we have the view already alluded to of a term of life impressed on a species.

But in the following note we get extinction connected with unfavourable variation, and thus a hint is given of natural selection:

“With respect to extinction, we can easily see that al variety of [the] ostrich (Petise), may not be well adapted, and thus perish out; or, on the other hand, like Orpheus (a Galapagos bird), being favourable, many might be produced. This requires [the] principle that the permanent variations produced by confined breeding and changing circumstances are continued and produced according to the adaptation of such circumstance, and therefore that death of species is a consequence (contrary to what would appear from America) of non-adaptation of circumstances."

'The first part of the next extract has a similar bearing. The end of the passage is of much interest, as showing that he had at this early date visions of the far-reaching character of the theory of evolution :

“With belief of transmutation and geographical grouping, we are led to endeavour to discover causes of change; the manner of adaptation (wish of parents ??), instinct and structure becomes full of speculation and lines of observation. View of generation being condensation,* test of highest organisation intelligible .... My theory would give zest to recent and fossil comparative anatomy ; it would lead to the study of instincts, heredity, and mind-heredity, whole [of] metaphysics.

"It would lead to closest examination of hybridity, regeneration, causes of change in order to know what we have come from and to what we tend to what circumstances favour crossing and what prevents it—this, and direct examination of direct passages of structure in species, might lead to laws of change, which would then be the main object of study, to guide our speculations."

The following two extracts have a similar interest ; the second is especially interesting, as it contains the germ of concluding sentence of the Origin of Species':t

"Before the attraction of gravity discovered it might have been said it was as great a difficulty to account for the movement of all (planets} by one law, as to account for each separate one; so to say that all mammalia were born from

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* I imagine him to mean that each generation is “condensed” to a small number of the best organized individuals.

+'Origin of Species' (edit. i.), p. 490 :—"There is a grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one ; and that whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved."

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