CRETACEODS AND TERTIARY FLORA. 



By Leo Lesqueeeux. 



INTRODUCTION. 



The present volume contains: 



1st. The materials referable to the Cretaceous Flora. 



The species recognized from specimens received since the publication 

 of the Annual Report of Dr. F. V. Hayden, 1874, are of course described 

 here, but it has been found advisable to add to them and to consider again 

 part of what has been published in that report as a Review of the Cre- 

 taceous Flora of North America; mentioning also the species described 

 by Professor Heer and Dr. Newberry from specimens obtained from the 

 Dakota Group. 



It is well known that the plants of the Cretaceous epoch, at least those 

 of a higher class, the Dycotyledons, have been barely discovered and 

 described in Europe, while the profusion of these vegetables in the Dakota 

 Group constitutes an original- illustration of a peculiar vegetation which, 

 for reasons explained hereafter, will be of great significance in the future. 

 From this consideration the exposition, in the same work, of all that is 

 known to this time of the North American Cretaceous Flora is greatly to the 

 advantage of vegetable paleontology both in this country and in Europe. 



2d. A description of a few species of plants of the Laramie Group, 

 which I persist in considering as Eocene. 



These species, added in this volume to the list of the plants already 

 -described from the same formation, were all obtained at Golden, Colorado, 

 from the locality where most of those published formerly were found by 

 myself. One, Oreodoxites plicatus, si fine Palm, represented by a number of 

 well-preserved though more or less fragmentary leaves, is of a peculiar type, 



