AMKRICAN GEOLOGY SURVEYS UNDER HAYDKN. 



599 



Fig. 102.— Frederic Miller Endlich, 



W. R. Taggert, assistant geologist; Henry W. Stuckle, assistant 

 topographer, and J. H. Batty, naturalist. The third or San Luis 

 division was in charge of A. D. Wilson, topographer, with George M. 

 Chittenden, assistant topographer, and Dr. F. M. Endlich, geologist. 

 The work of this year extended as far westward in Colorado as 

 Middle Park, the Elk Mountains, and the San Luis Park. It was 

 during this season's work that the peculiar 

 examples of subaerial erosion of Monument 

 Park in Colorado were described and fig- 

 ured, which have so frequently served the 

 purpose of reproduction in the text-books. 

 The wonderful instances of complete over- 

 turning of immense groups of beds, as 

 illustrated in the Elk Range, were again 



referred to, atten- 

 tion being called to 

 the fact that for 

 several miles there 

 is a double series 

 from the Silurian 

 up to the Creta- 

 ceous, inclusive, which had been thus in- 

 verted. In this report, too, were given the 

 examples of inversion in the Snow Mass 

 Range and the view on Roches Moutonnes 

 Creek, both of which have served their pur 

 pose in the text-books of Dana and Le Conte. 

 The question of the age of the lignite beds 

 occupied the attention of nearly all the work- 

 ers in the held (see p. 647). Lesquereux, in 

 his chapter on the lignite flora, argued in 

 favor of the Eocene and Miocene age of the 

 beds. Though not denying the presence of 

 animal Cretaceous remains in the lignite 

 strata, he regarded the "presence of some 

 scattered fragments of Cretaceous shells as of 

 little moment in comparison with the well- 

 marked characters of the flora.' 1 Meek's 

 invertebrate work, moreover, he regarded as 

 rather in favor of the Tertiary hypothesis. To Cope's conclusions 

 "that a Tertiary flora was contemporaneous with a Cretaceous fauna, 

 establishing an uninterrupted succession of life across what is gene- 

 rally regarded as one of the greatest breaks in geological time," he 

 took exception, as it did not appear to exactly conform to facts. 



Fig. 103.— Inverted beds of Jack 

 ass Creek. (After A. C. Peale.) 



