XXII 



BIOGRAPHICAL SKETCH OF JOHN BELL HATCHER. 



The following table exhibits Hatcher's views as to the sequence of the various sedimentary 

 rocks of Patagonia and their age as indicated by paleontologic and stratigraphic evidences: 



Sedimentary rocks of Patagonia. 



His observations thus included the Mesozoic section as far down as the Jurassic and, with 

 the exception of a few multituberculate teeth in the Guaranitic beds, completely excluded the 

 mammals from the Upper Cretaceous, where they had been placed. 



In 1902 Hatcher again began discussing the Upper Cretaceous vertebrate-bearing horizons 

 of North America, and especially the relations of the Judith River and Laramie beds. Already 

 (American Naturalist, February, 1S96) he had affirmed that the Judith River beds were 

 certainly older than the Ceratops beds of Converse County, Wyo., and that the dinosaurs from 

 the Judith River belonged to smaller and less specialized forms than those from the latter 

 locality. Osborn, without observing this note, had subsequently reached the same conclusion. 

 In an animated series of notes and papers Hatcher discussed this question, and finally in June, 

 1903, accompanied Mr. T. W. Stanton, paleontologist of the United States Geological Survey, 

 in a field study of the Judith River beds and associated formations in Montana and southern 

 Assiniboia. They demonstrated that the Judith River beds represent a fresh-water deposit 

 600 feet in thickness which is intercalated in the true marine beds of Fort Pierre age, which, 

 therefore, both underlie and overlie the Judith River. This conclusion entirely cleared up this 

 vexed question, explained the discrepancies in the notes of different observers, and established 

 the practical synchronism of these beds with the Belly River deposits of British Columbia, as 

 suggested on geological grounds by Dawson and on faunalistic grounds by Osborn and Lambe. 



Hatcher's chief contribution to the Jurassic is his admirable paper published in 1901, 

 "The Jurassic dinosaur deposits near Canyon City, Colo.," in which he shows the sequence in the 

 deposition and evolution of the dinosaurian remains found at this point and clearly states the 

 difficulties which arise in our attempts to correlate these strata with the Upper Jurassic or 

 Lower Cretaceous. His concluding paragraph, while not of final value, is so interesting and 

 suggestive that it may be quoted entire: 



