22 



University of California Publications. [Geology 



INTRODUCTION. 



The Tertiary fossil beds of northwestern Nevada were first 

 brought to the writer's attention in 1905 through Mr. Robert L. 

 Fulton, who kindly permitted the examination of several frag- 

 ments of bones and teeth obtained in Virgin Valley by Mr. Allan 

 C. Bragg, and given by him to Mr. Pulton. In the attempt to 

 obtain information regarding the geology of the region, the late 

 John A. Reid, then Professor at the University of Nevada, 

 assisted in every possible way. 



In June, 1906, the writer, in company with Felix T. Smith, 

 a student at the University of California, made a reconnaissance 

 of the Virgin Valley region and obtained a small collection of 

 fossils. In a brief statement of the results of this study pub- 

 lished by the writer 1 the formation in Virgin Valley was desig- 

 nated as the Virgin Valley Beds. It was considered as Miocene, 

 with the suggestion that the upper part of the series was prob- 

 ably not older than the Mascall stage of the John Day region. 



In a discussion of some of the ungulate material collected 

 largely in the older beds at Virgin Valley by Merriam and Smith 

 in 1906, J. W. Gidley 2 expressed the opinion that all of the 

 specimens in the collection examined represented middle or 

 lower Miocene, and that they might be somewhat older than the 

 Mascall. 



In the summer of 1909, Miss Annie M. Alexander very kindly 

 offered to organize and finance an expedition to Virgin Valley to 

 carry on the work which had been suggested by the reconnais- 

 sance in 1906. The party organized by Miss Alexander spent 

 three months in the field, and after working over the exposures 

 at Virgin Valley and Thousand Creek, the exploration was 

 extended to several localities near Soldier Meadows to the south 

 of Virgin Valley, where a number of new exposures of mammal 

 beds were discovered. 



The available information relating to the mammal beds of 

 the Virgin Valley and Thousand Creek region is presented in 



1 Science, n. s., 26, pp. 380-382. Sept. 20, 1907. 



2 Univ. Calif. Publ. Bull. Dept. Geol., 5, p. 242. 1908. 



