STRATIGRAPHY OF THE CERATOPS BEDS. 



131 



The total thickness of beds above the Fox Hills 

 fossils to this horizon is 705 feet and the average dip 

 is about 16 degrees northwest. The overlying beds, 

 though not well exposed, appear to have the same 

 steep dip in a belt nearly or quite a mile wide, so that 

 the thickness of upturned beds above the Fox Hills 

 fossiliferous zone is probably 1,500 to 2,000 feet. 



On comparing these sections with Mr Hatcher's 

 descriptions it is seen that the base of the Ceratops- 

 bearing beds is above the massive sandstones, on 

 about the same horizon as the brackish water Laramie 

 fossils and the lowest bed from which plants were ob- 

 tained. 



The dip rapidly decreases to the west and north- 

 west toward the middle of the basin, where the locali- 

 ties for the Ceratops vertebrate fauna are most numer- 

 ous, and over the larger part of the area the beds are 

 almost horizontal. 



The accompanying sketch section (figure 1) shows 

 the general structure and stratigraphy on a line ex- 

 tending northwesterly from the neighborhood of 

 Buck creek to a point northwest of Lightning creek. 

 The vertical scale and the dips are much exaggerated. 

 The actual length of the section is 12 or 15 miles. 



On the east side of Lance creek, nearly on the line 

 of the first local section and not more than a mile 

 north of the Fox Hills exposure, the dip is only 10 

 degrees. A few fossil plants were collected here, in- 

 cluding Menispermites n. sp., and an Equisetum (?), 



At a somewhat higher horizon, one and a half miles 

 southeast of the U-L ranch, where the dip is scarcely 

 perceptible, the following species of invertebrates 

 were collected : 



Anodonta parallela, White. 

 Sphserium sp. 



Tulotoma thornpsoni, White. 

 Campeloma multilineata, M. and H. 

 Campeloma producta, White (?) 

 Viviparus trochiformis, M. and H. 

 Physa copei, var. canadensis, Whiteaves. 

 Helix vetusta, M. and H. 

 Limnxa sp. 



n 

 3* 



k 



p 



o 

 o 

 m 



3 

 01 



•-I 

 n> 

 m 

 i-t- 



5' 



»• 3 



f 



2 



o 



ft 



n 



H 



n 



J* 

 £ 



p 

 o 



« <> 



o 



oq 



n 

 K 



S 



w 



o 



5 o 



° n 



n 

 *?. *"i 



o p 



6" 



o 



•d 

 en 



n 



0- 



3* 

 O 



N 



o 



3 

 O 



P 



n 



3* 

 P 



r* 



n 



■-t 



t> 

 p 

 n 

 p 



M 



O 



d 



w 





$ 





(-3 



to 



--&« 



ft 



a 



c^ 



IS 



r 



