A CATALOGUE OF THE CEETACEOUS AND TER- 
TIARY PLANTS OF NORTH AMERICA. 
By F. H. Knowlton. 
INTRODUCTION. 
This catalogue of the Cretaceous and Tertiary plants of North 
America is the outcome of the author's personal needs, and is pre- 
sented, even in its present somewhat imperfect form, in the hope that 
it may be of assistance to other workers in this field. 
The first catalogue of approximately this scope was published by 
Prof. Leo Lesquereux in the Tenth Annual Eeport of the United States 
Geological and Geographical Survey of the Territories 1 under the title 
Catalogue of the Cretaceous and Tertiary Plants of North America, 
with Keferences to the Descriptions. In this catalogue the species are 
arranged in botanical sequence. The Cretaceous flora embraced only 
157 species and the Tertiary flora 549 species, or a total of 706 for these 
two great geological systems. As a proof of the rapid growth of 
paleobotanical knowledge in this country during the twenty-one years 
between that and the present enumeration, it may be stated that the 
Potomac flora alone now numbers more species than the total Cre- 
taceous and Tertiary floras known to Lesquereux, and that the flora 
of the Dakota group has more than twice as many species (4G0) as the 
whole Cretaceous had, as then known. 
The only other catalogue is that of S. A. Miller, published in 1881 
under the title North American Mesozoic and Camozoic Geology and 
Palaeontology j or, An Abridged History of Our Knowledge of the 
Triassic, Jurassic, Cretaceous, and Tertiary Formations of this Conti- 
nent. This is hardly more than a crude compilation from that of Les- 
quereux and certain publications that had appeared between the date 
of that and the year 1881. 
A number of lists without references or synonymy have been pub- 
lished which embrace simply the names and in some cases the distri- 
bution of the species — such, for example, as Lesquereux's " Table of 
distribution of the species of fossil plants in the Tertiary formations 
Washington, 1876 [1878], pp. 487-520. 
