o o :^r T E N^ T s 



Pago. 



Note of Maj. J. W. Powell, Directoh of the Geological Survey iij 



Lettkr of Dr. F. V. IIayden to the Secretary of the Ixteiuor v 



LetTKU of TKAXSJIIITAL • 



Introduction , 



I. — The Flora of the Dakota Group 2 



General remarkB o 



Descriptiun and enumeration of species of the American Dakota Group formation 25 



Table of distribution of the plants of the Cret.iceous Cenomanian formation 93 



The relationship of the flora of the Dakota Group jgg 



II.— The Flora of the Laramie Group 109 



Table of distribution of the species of the Laramie Group. 115 



Description of species added to the flora of the Laramie Group 121 



III.— The Flora of the Green River Group 127 



Geological distribution of the measures I27 



Enumeration and description of the species of fossil plants known from the Green River Group .... 135 



General remarks oq- 



Table of distribution of the plants of the Green River and White River Groups 206 



Relationship of the local groups indicated by correlation of species 213 



IV. — The Miocene Flora 219 



Description of the Miocene species from specimens obtained in the so-called Bad Lauds of Dakota. 221 



Description of Miocene species of California and Oregon 239 



Contribution to the Miocene flora of Alaska 2.57 



Species of plants from the Chalk Blufis of California 265 



Table of distribution of the North American Miocene fossil plants 266 



Remarks on the species of Miocene plants 273 



Index 279 



Descriptions of plates follow page 283 



LIST OF ILX,XJSTRA.TION"S. 



Plates I-XVII I.— Fossil Plants from the Dakota Group— Cretaceous. 



Plates XI X-XX.— Fossil Plants from the Laramie Group. 



Plates XXl-XLV (A).— Fossil Plants from the Green River Group. 



Plate XLV (B).— Fossil Plants from the Ch.ilk Bluffs of Nevada County, California. 



Plates XL VI-XLIX.— Fossil Plants from the Bad Lands of Dakota. 



Plates I..-LIX. — Fossil Plants from the Miocene of California and Oregon. 



