14 FOSSIL FLORA OF THE JOHN DAY BASIN, OEEOON. [bull. 204. 



coiitirmcd the theory that Lesquercux had inadvertently confused at 

 least two localities under the name of Cheny Creek. The typical 

 matri.x at Cherry Creek is a hard, yellowish-brown sandstone, which 

 fractures yery irregularly, making- it difficult to obtain perfect impres- 

 sions. Only the species known to haye come from there, or pre- 

 served on matrix so similar as to leave no reasonable doubt that it 

 is the same, are included in the following- enumeration. 



As already stated, Dr. Merriam obtained small collections of fossil 

 plants during the field seasons of 1899 and 1900. These were submit- 

 ted to me for determination, and a more or less tentative report was 

 incorporated by Dr. Merriam in his report above mentioned on the 

 geology of the John Day Basin. 



During the field season of 1901 I visited the John Daj^ Basin under 

 the guidance of Dr. Merriam and made collections of plants at Cherry 

 Creek, Bridge Creek, and Van Horn's or Belshaw's ranch and vicinity. 

 At the close of the field season some weeks were spent in thoroughly 

 going over the type collections of plants in the paleontological museum 

 of the Univ^ersity of California. It was at this time that the fact was 

 developed that a part of the Van Horn's ranch material had been 

 included by Lesquereux in his Flora of the Auriferous Gravels of Cali- 

 fornia. Inasmuch as these species were mainly the ones upon which 

 rested the correlation between the beds in the John Day Basin and the 

 Auriferous gravels, the detection of the error was of the utmost 

 importance. 



GEOLOGICAL FEATURES OF THE JOHN DAY BASIN. 

 HISTORY OF GEOLOGICAL INVESTIGATION IN THE REGION. 



Considerable confusion and uncertainty have existed regarding 

 geological events and their sequence within this area, due in large 

 measure to the fact that observations were either hastily made during 

 brief reconnaissance trips through the region, or were confined to 

 the vicinity of the richer fossil deposits. Even at the present time 

 no detailed geological stud}^ of this region has been undertaken. By 

 far the most important contribution to the subject that has thus far 

 been made is that by Dr. John C. Merriam, in the paper already 

 referred to.^' Before passing to an exposition of his own views Dr. 

 Merriam presents the following brief summary of previous work: 



The first mention of the fossiliferous deposits in the John Day Basin which appears 

 in the literature was made by Dr. Joseph Leidy. In October, 1870, Dr. Leidy pre- 

 sented before the Philadelphia Academy of Sciences b a short paper, in which he 

 described "A collection of fossils recently received for examination through the 

 Smithsonian Institution, from Rev. Thomas Condon, of Dalles City, Oregon." The 



a A contribution to the geology of tlie John Day Basin: Univ. Cal., Bull. Dept. Geol., Vol. II, No. 9, 

 April, 1901, pp. 269-314. 

 bProc. Phila. Acad. Nat. Sci.,\ol. XXII, 1870, pp. 111-112. 



