FOSSIL PLANTS. 46i) 



Golden, Colo. — ( Jontinued. 



Hoyt's coal mine, 1 mile south of Golden. 



Murphy coal bank, Ralston Creek, north of Golden. 

 Boulder County: 



Coal miues near Erie, Boulder County. 



Coal mines on Coal Creek. 



Marshall's coal mine. 

 Morrison, Colo.: 



Mount Carbon; sandstone near coal scam. [Laramie.] 



White sandstone. [Dakota.] 

 Denver, < 'olo. : 



Sand Creek, near Denver. 

 Sedaha, Colo.: 



Quarry No. 1; 1,900 feet east of the Douglas coal mine. 



Quarry No. 2; 3,000 feet east of the Douglas coal mine. 



Douglas coal mine, and 150 feet east of main coal seam. 



HORIZONS INDICATED BY FOSSIL FLORA. 



The fossil plants of the Denver Basin belong- to three well-defined and 

 clearly differentiated horizons, viz, the Dakota group, Laramie, and the 

 more recently distinguished Denver beds. These horizons will be discussed 

 in ascending order, beginning, consequently, with the Dakota. 



DAKOTA liBOUP. 



With the exception of two species, found, according to Lesquereux, in 

 the vicinity of Golden, only one locality within the area lias afforded 

 plants of this horizon — the hard, white sandstone at Morrison. The plants 

 are not especially well preserved. The carbonaceous matter having almost 

 entirely disappeared, the leaves and stems remain as outlines that are often 

 faint and difficult to make out. It appears that only the best of this 

 material had been seen by Lesquereux previous to the publication of the 

 Cretaceous and Tertiary Floras, but he enumerated about 20 species, many 

 of which were new to science. After the donation of the material to the 

 National Museum, as above stated, it was all submitted to him with the 

 result of adding a number of species to the flora of this place. Idle total 

 number of species known from Morrison is 28. They are all enumerated 

 in the following table (p. 470), which also shows their distribution, if any, 

 outside of this area. 



