It is difficult to imagine that the change from wind or self-fertilization can, so to speak, commend itself to the flower on the score either of economy or success. If the anemophilous blossom must produce somewhat more pollen than the entomophilous, it saves the great expenditure of material and vital force requisite for the production of the large and conspicuous corolla. The one is fertilized by every wind that blows; the other, especially in the case of highly-specialized flowers like the orchids, may be incapable of fertilization except by a very few insects. The celebrated Madagascar orchid _Angræcum_ can be fertilized, it is said, only by a moth with a proboscis from ten to fourteen inches long--a moth so rare or local that it is as yet known to naturalists only by prophecy. It is difficult to suppose that it would be beneficial for the plant's chance of survival to exchange as the fertilizing agent the universal wind for this most localized insect. And here another line of evidence comes in and demands consideration. The face of Nature, as we now see it, has not been always exhibited by the world. The flora, like the fauna, of the world has changed: how has it changed as regards the beauty of the flowers? Does it give any testimony to that _becoming_ beautiful of the flowers of plants to which Mr. Darwin refers? The answer is not a very certain one, by reason of the imperfection of the geological record, of the probability that beautiful plants, if they had existed, and had been of a delicate structure, would have perished and left no trace behind. But so far as an answer can be given, it is in favour of the increase of floral beauty in the vegetable world. The earliest flower known (the _Pothocites Grantonii_) occurs in the coal measures; its flowers cannot have been other than inconspicuous in themselves, though it is possible that by grouping they were made more attractive to the eye; in the period of the growth of the coal, when this plant lived, the vast forests seem principally to have been composed of trees without conspicuous blossoms, huge club mosses and marestails, and many conifers; in the earlier periods of this earth we have no trace of conspicuous blossom, and it is not till the upper chalk that the oaks and myrtles and _Proteaceæ_ appear as denizens of the forests. In like manner, if we refer to the appearance of insects on the earth, we have no clear trace in very early strata of those classes of insects which now do the principal work of fertilization for our conspicuous flowers. In the coal measures there have been found insects of the scorpion, beetle, cockroach, grasshopper, ant, and neuropterous families; but of a butterfly or moth there is only evidence of great doubt. It seems probable, then, and one cannot say more, that with the progress of the ages, flowers, as a whole, have become more conspicuous and attractive. But if we inquire whether the dull flowers