we have in reality the well-known Fucus before us. Rushes, flags, and aquatic grasses may now be seen standing in diminutive tufts out of the water; and a terrestrial vegetation at least continues to exist, though it can scarce be said to thrive, on banks covered by the tide at full. The lacustrine flora increases, both in extent and luxuriance, as that of the sea diminishes; and in the upper reaches we fail to detect all trace of marine plants: the algæ, so luxuriant of growth along the straits of this “miniature Mediterranean,” altogether cease; and a semi-aquatic vegetation attains, in turn, to the state of fullest development any where permitted by the temperature of this northern locality. A memoir descriptive of the Loch of Stennis, and its productions, animal and vegetable, such as old Gilbert White of Selborne could have produced, would be at once a very valuable and curious document, important to the naturalist, and not without its use to the geological student. I know not how it may be with others; but the special phenomena connected with Orkney that most decidedly bore fruit in my mind, and to which my thoughts have most frequently reverted, were those exhibited in the neighborhood of Stromness. I would more particularly refer to the characteristic fragment of _Asterolepis_, which I detected in its lower flagstones, and to the curiously mixed, semi-marine, semi-lacustrine vegetation of the Loch of Stennis. Both seem to bear very directly on that development hypothesis,—fast spreading among an active and ingenious order of minds, both in Britain and America, and which has been long known on the Continent,—that would fain transfer the work of creation from the department of miracle to the province of natural law, and would strike down, in the process of removal, all the old landmarks, ethical and religious. THE DEVELOPMENT HYPOTHESIS, AND ITS CONSEQUENCES.