1896.] Laramie Mammals and Horned Dinosaurs. 115 



what fully. In speaking of the horned dinosaurs in the pub- 

 lication just cited he says: " The geological deposits, also, in 

 which their remains are found have been carefully explored 

 during the past season, and the known localities of importance 

 examined by the writer, to ascertain what other fossils occur 

 in them, and what were the special conditions which preserved 

 so many relics of this unique fauna. 



" The geological horizon of these strange reptiles is a distinct 

 one in the upper Cretaceous, and ha$ now been (raced nearly 

 eight hundred miles along the eastern flank of the Rocky Mount- 

 ains. It is marked almost everywhere by remains of these 

 reptiles, and hence the strata containing them may be called 

 the Ceratops beds. They are freshwater or brackish deposits, 

 which form a part of the so-called Laramie, hut are below the 

 uppermost beds referred to that group. In some places, at least, 

 they rest upon marine beds which contain invertebrate fossils 

 characteristic of the Fox Hills deposits." Italics mine. 



If we accept literally Marsh's statement that the Ceratops 

 beds have been traced for eight hundred miles along the east- 

 ern flank of the Rocky Mountains, it will be necessary to sup- 

 pose that he includes in the Ceratops beds not only the beds in 

 Converse Co., Wyoming, but also the Bison beds {Denver beds <>/ 

 Cross) at Denver, and the Judith River beds on the upper Mis- 

 souri These are very widely separated localities, and no 

 attempt has ever been made to trace the continuity of the 

 strata from the one to the other, nor is it at all probable that 

 such an attempt would meet with success. Professor Marsh 

 did in the autumn of 1889 spend nearly two days in the Con- 

 verse Co. locality, and again in 1891 he spent one full day in 

 the same locality ; but his time was occupied in visiting a few 

 of the localities in which dinosaui skulls and skeletons and 

 Laramie mammals had been found. No time was taken to 

 determine the upper and lower limits of the beds or to trace 

 the outcrops of the strata. After his visit in 1889 when he 

 spent nearly two days with our party in the Converse Co. 

 locality, he took the train for Denver, and in the company of Mr. 

 George L. Cannon of that city, he spent one-half day examin- 

 ing the Bison beds (Denver beds). This constitutes Professor 



