His progeny or kind may have survived such change, have migrated landward; there is no ground for inferring the ancient race to have been swept away by a "flood." The tranquil or non-cataclysmal movements and operations resulting in a new surface or stratum went on, but with an accessory evidence of the progress of time.
Our earth received, as of yore, its solar, lunar, and atmospheric influences; but its surface at the locality in question continued slowly to subside—so gradually, indeed, as to admit, at successive periods, of the growth of trees and of generations of those low organized plants the débris of which constitute "peat."
It would seem at least that, for a time, the surface of the sandy soil (Table of Strata, no. 9) admitted of the growth thereon of trees, as testified by portions of their ligneous trunks and branches, now blackened and decayed (ib. 9′). Their destruction was inevitable when the surface sank and became overflowed, receiving then deposits of mud (ib. 8). But there were intervals of time, in which a Sphagnum or Hypericum[1] could root itself in such parts of the mud-deposit as might be exposed to sun and air; for in this stratum peat occurs associated with the argillaceous matter; and this combination has a vertical extent of nearly four feet. The general movement of subsidence being resumed, no. 8 is overflowed by waters which leave upon it nearly two feet of pure mud, no. 7. Then a retreat of the overflowing waters with exposure of the surface allows of successive growths and decadence of the plants constituting peat, of which the stratum no. 6, nearly four
- ↑ Hypericum elodes.