SOUTH DAKOTA SCHOOL OF MINES 27 



represented this institution in its field investigations. 

 Backed by abundant means and made up of capable investi- 

 gators, they have been able to carry home a large amount 

 of extraordinarily valuable material. This has given op- 

 portunity to establish more accurately the details of 

 stratigraphy and correlation and to indicate with greater 

 certainty the characteristics and habits of the various 

 animals while in the living state. The years in which par- 

 ties have been in the field, either in South Dakota or north- 

 western Nebraska are 1892, '93, '94, '97, '03, '06, '08, '11, '12, 

 '13, '14, '16. Under the direction of Prof. EL F. Osborn, (Plate 

 8), Curator of the Department of Vertebrate Paleontology, 

 earlier a co-worker with Prof. Scott in the Princeton investi- 

 gations, many of the best preserved skeletons complete in 

 practically every detail and mounted with the greatest skill, 

 have been clothed with flesh, life and activity. Eeproduc- 

 tions of a number of these, reference to which is made on 

 other pages, are given in this book. 



The University of Nebraska sent expeditions into the 

 field, the parties being under direction of Prof. E. H. Bar- 

 bour in 1892, '94, '95, and '97, '05, '07, '08 and later. Much of 

 their collecting was done in northwestern Nebraska, but a 

 considerable part of it in South Dakota and Wyoming. Prof. 

 J. E. Todd of the University of South Dakota, spent a brief 

 time in the field in 1894. He made a second visit, accom- 

 panied by several students in 1896. The University has 

 more recently carried on additional investigations but the 

 publications issued have been largely in connection with 

 the fauna and flora of the present day. 



New impetus was given the geological and paleontolo- 

 gical work, particularly among the Miocene formations of 

 northwestern Nebraska and eastern Wyoming, by the in- 

 auguration in 1902 of explorations by the Carnegie Museum 

 of Pittsburg. This has continued to the present time. Mr. 

 Hatcher directed much of the earlier work, while later, Mr. 

 O. A. Peterson has had charge of it. This museum, as in the 

 case of the American Museum, has been particularly success- 

 ful, and many new and strange species have been discovered 

 and described. A discovery of special note is that of the 

 rich and important bone deposits near Agate Springs found 

 in 1904. 



