The animals do not transmit their knowledge; that which each individual accumulates dies with him.
The loss per revolution is exceedingly small, but it accumulates, and at any era the total loss is the sum of all the losses preceding it.
Naturally, any man who has been President, and filled other positions, accumulates such things, with scant regard to his own personal merits.
On the poorest, thinnest ground it only reaches a foot or two; but in hollow places where leaf-mould accumulates and surface soil has washed in and made a better depth, it grows from six feet to eight feet high, and when straggling up through bushes to get to the light a frond will sometimes measure as much as twelve feet.