STRATIGRAPHIC POSITION OF LANCE FORMATION 369 



brackish-water forms. It does not appear that they have ever 

 been found at a greater distance than 12 or 15 feet above the top 

 of the Fox Hills, and since it further appears that in none of the 

 four sections given 1 does the Fox Hills exceed 115 feet in thickness, 

 there is every probability that they were re-deposited in the chan- 

 neled upper surface of the Fox Hills and that they did not live in 

 association with the brackish-water forms with which they are now 

 found entombed. 



The plant collections obtained from the Lance formation by 

 Mr. Calvert and the members of the several parties under his 

 charge show conclusively that the relation of this flora is unmis- 

 takably with the Fort Union. In fact with the information at 

 hand regarding distribution it is practically impossible without 

 stratigraphic data to distinguish between the flora of the Lance 

 formation and that of the acknowledged Fort Union. The lists 

 of these collections follow: 



[5437]. NW J Sec. 5, T2N, R88W, S. Dakota. North bank of Cannonball 

 River, at McCord coal-bank, 150 feet above base of beds. 



Sequoia nordenskioldi Heer 



Thuya interrupta Newb. 



Glyptostrobus europaeus Unger 



Populus speciosa Newb. 



Populus amblyrhyncha Ward 



Paliurus colombi ? Heer 



Sapindus grandifoliolus Ward 



Celastrus alnifolia ? Ward 



Juglans sp. ? 



2 new forms, gen. ? 

 [5443]. SW j Sec. 23, T23N, R21E, Black Hills Meridian, 150 feet above base 



Sequoia nordenskioldi Heer 

 Leguminosites arachnioides Lesq. 

 [5444]. Near \ cor. E. side Sec. 13, T22N, R22E. Black Hills Meridian. 125 

 feet above base of beds. 



2 or 3 of same species as unnamed forms from the "somber beds" at 

 Glendive, Montana. 



[5430]. Rattlesnake Butte, Cheyenne Indian Reservation, S. Dakota. 100 

 feet above base of beds. 



Glyptostrobus europaeus Newb. 

 Taxodium occidentale Newb. 



1 Am. Jour. Sci., XXX (1910), 174-77. 



