HELL CREEK BEDS, CERATOPS BEDS AND EQUIVALENTS 213 



tion the sandstones are usually fine-grained and massive, and sand- 

 stone concretions are of frequent occurrence. The line between 

 the lower and upper members is a lithologic one, the sedimentation 

 being continuous. 



At various localities in the Basin vertebrate remains have been 

 obtained in this lower member, but they are usually so fragmentary 

 that little can be said concerning them beyond the fact that they be- 

 long to dinosaurs. Plants are abundant in many places, as the fol- 

 lowing lists attest. 



The following localities for plants are known within the Bighorn 

 Basin: 



Near I o P. O., Bighorn County, Wyoming; above 500 feet above base of 

 beds. 



Onodea sensibilis fossilis Newb. 



Sequoia nordenskioldi Heer. 



Sequoia sp. 



Protophyllocladus? sp. new. 



Popidus cuneata Newb. 



Populus daphnogenoides Ward. 



Popidiis arctica Heer of Lesq. 



Populus n. sp. 



Populus amblyrhyncha Ward. 



Juglans sp. 



Corylus americana Wa'ter. 



Platanus haydenii Newb. 



Sapindus grandifoHoliis Ward. 



Celaslrus taurinensis Ward. 



Celastrus sp. 



Paliurus pulcherrimus Ward. 



Pal urus sp. 



Diospyros sp. 

 Two miles north of Ilo P. O., Bighorn County. 



Ginkgo adiantoides (Ung!) Heer. 



Populus amblyrhyncha Ward. 



Quercus sp. 



Platanus nobilis Newb. 



Magnolia tenuinervis? Lesq. 



Ficus sp. (type of F. planicostaia). 



Celas rus sp. 



Berchemia midtinervis Al. Br. 



Viburnum newberryanum Ward. 



Viburmim antiquum (Newb.) Hollick. 

 Twelve miles west of Ilo P. O., Bighorn County. 



Cocculus havdcnianus Ward. 



