116 Cincinnati Society of Natural History. 



well, 16 beds of coal making 48 feel in thickness were passed at 728 

 feet, and at 1,180 feet the sandstone of the Lower Lignitic had not 

 been pierced. He found a remarkable analogy, not to sa}' identity, 

 between the 547 feet of measures above the lignite beds at Evauston 

 and the conglomerate which tops the Lignitic at Colorado Springs and 

 other places. 



The masterl}^ review of the Ligniitic Group, by Prof. Le&quereux, 

 lead bim to the conclusion that it is of Eocene age. He said that the 

 Upper Cretaceous is positivel}^ characterized as a deep marine forma- 

 tion. Immediately over it, the sandstone shows, in its remains, the 

 result of the upheaval of a wide surface exposed to shallow marine 

 action, as indicated by fucoidal life. The upheaval continuing, this, 

 area is brought out of marine influence to be exix)sed to that of the 

 atmosphere. It is a new land, cut in basins of various sizes, where 

 fresh water is by and b}^ substituted to brine, where vegetable life 

 of another character appears, where swamps are filling with cla}' and 

 floating plants, where peat-bogs in their growth form deposits of com- 

 bustible matter, etc. To suppose that the marine action is totally 

 banished from such a land would demand the absurd admission of an 

 absolutely flat surface. Of course estuaries penetrate into it at manj^ 

 places; their waters feeding marine species, brackish shells; their 

 bayous inhabited by Saurians, and their remains mixed with leaves 

 of the trees growing on the borders and preserved together in a fossil 

 state, without impairing the true character of the formation by what 

 palaeontology considers as types of diff'erent ages. The surface of the 

 Eocene sandstone, before its separation from marine influence, was, of 

 course, uneven. This sandstone has, therefore, the general characters- 

 of the Eocene, while in some troughs, Cretaceous species, still living 

 in deep water, may have left their remains in the sand. Even if these 

 remains were numerous, their presence does not change the age of the 

 formation. But on this subject, and in comparing our Eocene sand- 

 stone to the other groups established by g-eologv, we find, in its abrupt 

 and permanent separation from the Cretaceous, its lithological com- 

 pounds, its total barrenness from animal remains, at least generall}'^ 

 and the homogeiieit}' of its flora, reliable and constant characters 

 better defined than in any geological division admitted by science. 

 This sandstone formation is inexplicable. It can be compared to 

 nothing but the millstone-grit of the Carboniferous epoch. How 

 to explain wh}^ at once, animal life seems to disappear from the 

 bottom of the sea, to be superseded b}' marine vegetation? May this 

 change have been caused^ perhaps, by a rapid increase of temperature- 



