PALEONTOLOGY OF THE BOULDER AREA 



By Junius Henderson 



This paper deals only with fossil species either known or suspected 

 to exist within a few miles of the University, and is based chiefly upon 

 material in the University Museum, though in its preparation a number 

 of private collections have been examined and much material studied in 

 the field. Most of the formations of the region are not well adapted for 

 the preservation of organic remains, so that many of the fossils are in 

 such condition that identification is difficult or impossible. Dr. T. W. 

 Stanton, of the United States Geological Survey, has rendered valuable 

 assistance in the determination of difficult material, and other friends 

 of the University have made a good collection possible by their con- 

 tributions. Much remains yet to be done to complete the paleonto- 

 logical collections, and the alumni and other friends of the institution 

 can greatly aid in the work, bearing constantly in mind that the value 

 of fossils depends largely upon the exactness of the data as to the locality 

 and conditions under which they are found. Some good material has 

 been rejected in the preparation of this paper because of the uncer- 

 tainty as to whether it was found "in place" or lying loose upon the 

 surface, where it may have been carelessly thrown by someone or depos- 

 ited by some of the natural methods of transportation. 



The western American geological column from the Permian upward 

 is as follows, in their order of occurrence, reading the column from the 

 most recent downward: 



Cenozoic 

 ( Recent 

 < Quaternary 

 ( Tertiary 



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