VERTEBEATE PALEONTOLOGY 243 



Museum in Pittsburgh in 1900, Hatcher carried forward 

 the work of exploration and collecting begun for that 

 institution by Wortman, and as a partial result prepared 

 many papers, the principal ones being memoirs on the 

 dinosaurs Haplocanthosaurus and Diplodocus. In 1903, 

 with T. W. Stanton of the United States Geological Sur- 

 vey, Hatcher explored the Judith River beds and together 

 they settled the vexatious problem of their age, the 

 published results appearing in 1905, after Hatcher's 

 death. His last piece of research, begun in 1902 and 

 continued until his death in 1904, was an elaborate mono- 

 graph on the Ceratopsia, one of the many projected by 

 Marsh. Of this memoir Hatcher had completed some 

 150 printed quarto pages, giving a rare insight into the 

 anatomy of these strange forms. The final chapters, 

 however, which were based very largely upon Hatcher's 

 own opinions, had to be prepared by another hand. 



Despite his early death, therefore, Hatcher rendered 

 a very signal service to American paleontology in 

 exploration, stratigraphy, morphology, and systematic 

 revision and his activity in planning new fields of 

 research, such, for instance, as the exploration of the 

 Antarctic continent, gave promise of further high attain- 

 ment, when his hand was arrested by death. 



Summary. 



It is not surprising that American vertebrate paleontol- 

 ogy has arisen to so high a plane, when one considers the 

 material at its disposal. Having a vast and virgin field 

 for exploration, a sufficient number of collectors, some of 

 whom have devoted much of their lives to the work, and 

 a refinement of technique that permitted the preservation 

 of the fragmental and ill conserved as well as the finer 

 specimens, the results could hardly have been otherwise. 

 Thus it has been possible to secure material almost 

 unique throughout the world for extent, for complete- 

 ness, and for variety. To this must be added a certain 

 American daring in the matter of the restoration of miss- 

 ing portions, both of the individual bones and of the 

 skeleton as a whole, such as European conservatism will 

 not as a rule permit. This work has for the most part 

 been done after the most painstaking comparison and 



