Nevertheless, soon or late it must inevitably grow old and vanish.

During the calm Indian summer, scarce a sand-grain moves around its banks, but in flood-times and storm-times, soil is washed forward upon it and laid in successive sheets around its gently sloping rim, and is gradually extended to the center, making it dryer.

Through a considerable period the meadow vegetation is not greatly affected thereby, for it gradually rises with the rising ground, keeping on the surface like water-plants rising on the swell of waves.

But at length the elevation of the meadow-land goes on so far as to produce too dry a soil for the specific meadow-plants, when, of course, they have to give up their places to others fitted for the new conditions.

The most characteristic of the newcomers at this elevation above the sea are principally sun-loving gilias, eriogonae, and compositae, and finally forest-trees.