A very important truth is contained in the expression "after its kind"--that is, after its _species_; for the Hebrew "_min_," used here, has strictly this sense, and, like the Greek _idea_ and the Latin _species_, conveys the notion of form as well as that of kind. It is used to denote species of animals, in Leviticus i., 14, and in Deuteronomy xiv., 15. We are taught by this statement that plants were created each kind by itself; and that creation was not a sort of slump-work to be perfected by the operation of a law of development, as fancied by some modern speculators. In this assertion of the distinctness of species, and the production of each as a distinct part of the creative plan, revelation tallies perfectly with the conclusions of natural science, which lead us to believe that each species, as observed by us, is permanently reproductive, variable within narrow limits, and incapable of permanent intermixture with other species; and though hypotheses of modification by descent, and of the production of new species by such modification, may be formed, they are not in accordance with experience, and are still among the unproved speculations which haunt the outskirts of true science. We shall be better prepared, however, to weigh the relations of such hypotheses to our revelation of origins when we shall have reached the period of the introduction of animal life. Some additional facts contained in the recapitulation of the creative work in Chapter II. may very properly be considered here, as they seem to refer to the climatal conditions of the earth during the growth of the most ancient vegetation, and before the final adjustment of the astronomical relations of the earth on the fourth day. "And every shrub of the land before it was on the earth, and every herb of the land before it sprung up. For the Lord God had not caused it to rain on the earth, and there was not a man to till the ground; but a mist ascended from the earth and watered the whole surface of the ground." This has been supposed to be a description of the state of the earth during the whole period anterior to the fall of man. There is, however, no Scripture evidence of this; and geology informs us that rain fell as at present far back in the Palaeozoic period, countless ages before the creation of man or the existing animals. Although, however, such a condition of the earth as that stated in these verses has not been known in any geological period, yet it is not inconceivable, but in reality corresponds with the other conditions of nature likely to have prevailed on the third day, as described in Genesis. The land of this period, we may suppose, was not very extensive nor very elevated. Hence the temperature would be uniform and the air moist. The luminous and calorific matter connected with the sun still occupied a large space, and therefore diffused heat and light more uniformly than at present. The internal heat of the earth