T 
Bibliographical Notice. 487 
the ae wall of the West that Pennsylvania exerts over all the con- 
us States.” The fossil flora of these Lignites ee by 
aissim made by Drs. Hayden and Leconte, and determined by 
Professor Lesquereux in 1868) is enumerated at pages 95-97; and 
Tepecik rar Tertiary age, Dr. Hayden says, at p. 97 :— 
* In conclusion, I beg leave to say that, while I have the most 
profound peepest for the labours of my fellow geologists in the same 
eld, I differ with them somewhat, simply because the evidence, to 
my mind, poin ats in a different direction. In various portions of the 
Laramie Plains, Colorado, Raton Hills, &e., I have observed between 
the well-defined Cretaceous and Tertia ary beds a group of strata, 
w s 
these beds I were to find some purely marine remains, even Inoceramus 
or Baculites, I should then call them transition beds, in accordance 
with the evidence of the continuous uninterrupted growth of the 
continent from the Citic through the Tertiary period. There 
beds, and no evidence of any change in sediments or any catastrophe 
sufficient to account for the sudden and apparently agre destruc- 
tion of organic life at the close of the Cretaceous peri 
examinations of the coal-formations over so vast an ek Ihave never 
yet seen a trace of a Cretaceous fossil in any strata above the coal.” 
the widely spread Tertiary deposits dacs along the eastern 
side of the Rocky Mountains, and mainly consisting of limited, though 
grand, lacustrine accumulations, but possibly here and there defined 
new by denudation, Dr. Hayden enumerates many local groups, 
which it is impossible at present to collate in detail. Of these, 
arranged provisionally, there are, belonging to the Upper Tertiary, 
the :— 
Salt-Lake group (1000 to 1200 feet of sandstones and marls) ; 
Bridger group (upward continuation of the Green-River group) ; 
Arkansas marls and Santa-Fé marls; and the Loup-River group, 
with remains of “ Aa foxes, tigers, hyenas, camels, horses, 
mastodons, elephan 
To the Middle Tels belong the 
Echo-Caüon group, 9000 to 5000 feet thick, including conglo- 
merates from 1500 to 2000 feet thick ; Wasatch group, reddish and 
variegated sands and clays, west of the Bridger group; Green-River 
shales, containing asphaltic shales, with fishes, insects, m and 
next below the Bridger group; Washekee group, with im 
nite; Gallisteo sands, with silicified wood, overlying ie "Miser. 
Mountain group; Monument-Creek group ; White-River group (with 
Upper Tertiaries on it), covering at least 150,000 square miles, 
* remar a pi as one of the most wonderful deposits of gums mam- 
malia on the globe," and of paray freshwater origin *; the 
Wind-River group, of limited e 
* See Ann. & Mag. Nat. Hist. ser. 3. vol. xi. pp. 976, 377. 
