We cannot here assign particularly the reasons for this opinion.  But we notice that the way in which varieties make their appearance strongly suggests it.  The variations of plants which spring up in a seed-bed, for instance, seem to be in no assignable relation to the external conditions.  They arise, as we say, spontaneously, and either with decided characters from the first, or with obvious tendencies in one or few directions.  The occult power, whatever it be, does not seem in any given case to act vaguely, producing all sorts of variations from a common centre, to be reduced by the struggle for life to fewness and the appearance of order; there are, rather, orderly indications from the first.  The variations of which we speak, as originating in no obvious casual relation to the external conditions, do not include dwarfed or starved, and gigantesque or luxuriant forms, and those drawn up or expanded on the one hand, or contracted and hardened on the other, by the direct difference in the supply of food and moisture, light and heat.  Here the action of the environment is both obvious and direct.  But such cases do not account for much in evolution.

Moreover, while we see how the mere struggle and interplay among occurring forms may improve them and lead them on, we cannot well imagine how the adaptations which arrest our attention are thereby secured.  Our difficulty, let it be understood, is not about the natural origination of organs.  To the triumphant outcry, “How can an organ, such as an eye, be formed under Nature?” we would respond with a parallel question, How can a complex and elaborate organ, such as a nettle-sting, be formed under Nature?  But it is so formed.  In the same species some individuals have these exquisitely-constructed organs and some have not.  And so of other glands, the structure and adaptation of which, when looked into, appear to be as wonderful as anything in Nature.  The impossibility lies in conceiving how the obvious purpose was effectuated under natural selection alone.  This, under our view, any amount of gradation in a series of forms goes a small way in explaining.  The transit of a young flounder’s eye across the head is a capital instance of a wonderful thing done under Nature, and done unaccountably.

But simpler correlations are involved in similar difficulty.  The superabundance of the pollen of pine-trees above referred to, and in oak-trees, is correlated with chance fertilization under the winds.  In the analogous instance of willows a diminished amount of pollen is correlated with direct transportation by insects.  Even in so simple a case as this it is not easy to see how this difference in the conveyance would reduce the quantity of pollen produced.  It is, we know, in the very alphabet of Darwinism that if a male willow-tree should produce a smaller amount of pollen, and if this pollen communicated to the offspring of the female flowers it fertilized a similar tendency (as it might), this male progeny