DAVIS, — ROCKY MOUNTAIN TERTIARIES. 349 



prominent among whom must be mentioned Ilayden, Newberry, and 

 King" (177). " Extensive lakes were formed in the depressions of the 

 Laramie and older beds. . . . After an interval of time another series 

 of lakes was formed, which have left their deposits over a wider extent 

 of the continent than have those of any other epoch. These constitute 

 the beds of the Loup fork period" (179). 



Many explicit quotations may be made from King's writings. In 

 those here following, the page numbers refer to the first volume of the 

 Fortieth Parallel Survey reports. The Vermillion creek beds in the 

 Green river basin are explained by accumulation in a depression " occu- 

 pied by an early Eocene lake, whose northern portion corresponded with 

 approximate accuracy to the present drainage-basin of Green river" 

 (359). After a description of localities, the author states that " from 

 the outcrops thus broadly sketched, it is clear that a single lake extended 

 from longitude 106° 30' to 112'^, stretching northward probably over 

 the greater part of the Green river basin and southward to an unknown 

 distance" (374). Reference is later made to the "great lake of the 

 Green river period" (393). King's recapitulation is as follows: — 

 " Tertiary time in the region of the Fortieth parallel is therefore repre- 

 sented by nine lakes : four Eocene lakes which occupied the middle 

 Cordilleras . . . ; two Miocene lakes, one in the province of the Plains, 

 the other in eastern Oregon and western Nevada ; and, lastly, the three 

 I'liocene lakes " (457). 



The early pages of Marsh's monograph on the Dinocerata abounds in 

 references to Tertiary lakes. The Eocene lake of the Green river basin 

 "remained a lake so long that the deposits formed in it, during Eocene 

 time, reached a vertical thickness of more than a mile. ... As these 

 [Rocky and Wahsatch] mountain chains were elevated, the inclosed 

 Cretaceous sea, cut off from the ocean, gradually freshened, and formed 

 these extensive lakes, while the surrounding land was covered with a lux- 

 uriant tropical vegetation, and with many strange forms of animal life." 

 The Dinocerata " which nearly equalled the elephant in size, roamed in 

 great numbers about the borders of the ancient tropical lake in which 

 many of them were entombed" (U. S. G. 8. Monogr., x, 1886, 1, 6). 



Button states that " The Tertiary system of the Plateau country [of 

 Utah] is lacustrine throughout, with the exception of a few layers near 

 the base of the series, which have yielded estuarine fossils. The widely 

 varying strata were accumulated upon the bottom of a lake of vast 

 dimensions" (Geol. High Plateaus of Utah, 158). The strata here 

 referred to are chiefly marls and hence may be largely lacustrine, but 



