Origin of Species Variorum

have overrated the importance of divergence of character (in which, however, he apparently believes), and that convergence of character, as it may be called, has likewise played a part. This is an intricate subject which need not be fully discussed. I will only remark that if two species of two allied genera, both produced a number of new and divergent species, I can believe that they might sometimes approach each other so closely that they would for convenience sake be classed in the same new genus, and thus two genera would converge into one; but from the strength of the principle of inheritance, and from the two parent-species already differing and consequently tending to vary in a somewhat different manner, it seems hardly credible that the two new groups would not at least form distinct sections in the genus. ↑

Mr. Watson has also objected that the continued action of natural selection with divergence of character will tend to make an indefinite number of specific forms. As far as mere inorganic conditions are concerned, it seems probable that a sufficient number of species would soon become adapted to all considerable diversities of heat, moisture, &c.; but I fully admit that the mutual relations of organic beings are more important; and as the number of species in any country goes on increasing, the organic conditions of life .. become more and more complex. Consequently there seems at first sight .. no limit to the amount of profitable diversification of structure, and therefore no limit to the number of species which might be produced. We do not know that even the most prolific area is fully stocked with specific forms: at the Cape of Good Hope and in Australia, which support such an astonishing number of species, many European plants have become naturalised. But geology shows us, that from an early part of the long tertiary period