J. G.
March 10, 1904.
PREFACE TO THE SECOND EDITION
IN this edition, which has been thoroughly revised throughout, a few corrections have had to be made, especially in the Index, and in one or two instances alterations or additions have appeared advisable for the sake of clearness or accuracy of expression. Nothing has, however, as yet been brought to the author's notice which affects any substantial point in what he has written.
July 28, 1904.
PREFACE TO THE THIRD EDITION
THIS edition has again been thoroughly revised, and some new matter appended which bears on various points raised in the original volume, especially the establishment of the important group of the Cycado-filices, as affecting the succession of plant life on the earth, and recent evidence concerning the pedigree of the horse.
December 21, 1906.