Note 185 — Chapter XIII · THE 'ORIGIN OF SPECIES'—REVIEWS AND CRITICISMS—ADHESIONS AND ATTACKS.

This refers to the passage in the Origin of Species (2nd edit. p. 285) in which the lapse of time implied by the denudation of the Weald is discussed. The discussion closes with the sentence: "So that it is not improbable that a longer period than 300 million years has elapsed since the latter part of the Secondary period." This passage is omitted in the later editions of the Origin, against the advice of some of his friends, as appears from the pencil notes in my father's copy of the 2nd edition.