LVI INTRODUCTORY REMARKS. 



information in regard to the existence of lignite (stone-coal, as they called it) 

 in the Upper Missouri country, 'though their report gives no suggestions in 

 regard to its geological relations. 



In 1843, however, Mr. Edwin Harris, who ascended the Missouri to the 

 mouth of the Yellowstone, with Audubon, the ornithologist, evidently gave 

 more attention to the geology of this region. On his return, in 1845, he 

 published some remarks on this subject in the Proceedings of the Phila- 

 delphia Academy of Natural Sciences.* He also brought back a lew fossils 

 from the beds near Fort Union, that were submitted to a committee of the 

 Academy, consisting of Dr. S. G. Morton, Prof. Henry D. Rogers, and Walter 

 R. Johnson, who reported that they were fresh-water shells of the genera 

 Lymncca, Pkinorb'ts, Anodonta, etc. They also mention the occurrence in 

 the collection of leaves of trees, and express the opinion that the beds from 

 which these shells and leaves were collected belong to the Tertiary epoch.f 

 This seems to have been the first published opinion in regard to the age of 

 this formation. 



In 1849, Dr. John Evans traced these lignite strata from below Fort 

 Clarke on the Missouri to a locality twenty miles below the mouth of Yel- 

 lowstone River; and, in 1850, Mr Thaddeus A. Culbertson, who visited this 

 country under the auspices of the Smithsonian Institution, also saw these 

 deposits at a few localities above Fort Union. These gentlemen, however, 

 brought no fossils from these rocks, nor did they publish any sections. 



As. the expedition of Dr. Hayden and the writer, sent by Professor Hall 

 in 1853, did not visit any of the districts occupied by these beds, of course 

 no additional information in regard to them was thereby obtained. 



Most of the years 1854 and 1855, however, were, as elsewhere stated, 

 spent by Dr. Hayden in exploring this country on his own account, and still 

 later, as geologist of Government expeditions under the command of Lieu- 

 tenant Warren and Captain Raynolds. During Dr. Hayden's sojourn in this 

 country, he collected many fossils from these lignite-bearing strata, both 

 animal and vegetable. The vertebrate remains were studied by Professor 

 Leidy and the plants by Dr. Newberry, while brief preliminary descriptions 

 of the invertebrates were published in the joint names of Meek and Hayden 

 in the Proceedings of the Philadelphia Academy for 1S5G. All the parties 

 concurred in referring Ihese deposits to the Tertiary; Dr. Newberry even 



* Proceed. Acad., 1845, - i35. t Proceed. Acad., 1845, £Ji). 



