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BY MEANS OF NATURAL SELECTION, OR THE
PRESERVATION OF FA-VORED RACES IN
THE STRUGGLE FOR LIFE

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vsriability—Indlvidital difierences—Doubtful species—Wide ranging, much

diffused, and common species, vary most—Species of the larger genera

in each country vary more frequently than the species of the smaller

genera—Many of the species of the larger genera resemble varieties in

being very closely, but unequally, related to each other, and in having

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restricted ranges .

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