→ a far 1859 1860 |
a 1861 1866 |
an equally or 1869 1872 |
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Guided by theoretical considerations, I thought that some interesting results might be obtained in regard to the nature and relations of the species which vary most, by tabulating all the varieties in several well-worked floras. At first this seemed a simple task; but Mr. H. C.
to whom I am much indebted for valuable advice and assistance on this subject, soon convinced me that there were many difficulties, as did subsequently Dr. Hooker, even in stronger terms. I shall reserve for
future work the discussion of these difficulties, and the tables
of the proportional numbers of the varying species. Dr. Hooker permits me to add, that after having carefully read my manuscript, and examined the tables, he thinks that the following statements are fairly well established. The whole subject, however, treated as it necessarily here is with much brevity, is rather perplexing, and allusions cannot be avoided to the "struggle for existence," "divergence of character," and other questions, hereafter to be discussed. |
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Candolle and others have shown that plants which have very wide ranges generally present varieties; and this might have been expected, as they
exposed to diverse physical conditions, and as they come into competition (which, as we shall hereafter see, is
→a far
more important circumstance) with different sets of organic beings. But my tables further show that, in any limited country, the species which are
common, that is abound most in individuals, and the species which are most widely diffused within their own country (and this is a different consideration from wide range, and to a certain extent from commonness),
give rise to varieties sufficiently well-marked to have been recorded in botanical works. Hence it is the most flourishing, or, as they may be called, the dominant
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