The fallen trees not completely covered by water are soon overgrown with mosses; aquatic and semiaquatic plants propagate themselves, and spread until they more or less completely fill up the space occupied by the water, and the surface is gradually converted from a pond to a quaking morass.
"The Earth as Modified by Human Action"
George P. Marsh
A rhinoceros, semiaquatic in habits, with curved tusks, resembling in aspect the hippopotamus, lived along the water courses of the plains east of the Rockies, and its bones are now found by the thousands in the Miocene of Kansas.
"The Elements of Geology"
William Harmon Norton