Lull — Development of Vertebrate Paleontology. 211 



Material was now accumulating' so fast as to necessi- 

 tate the concentration of Cope's own time on research, 

 so that, while he continued to make brief journeys to the 

 West, the real work of exploration was delegated to 

 Charles H. Sternberg and J. L. Wortman, both of whom 

 became subsequently very well known, the former as a 

 collector whose active service has not yet ceased, the 

 latter as an explorer and later an investigator of 

 extremely high promise. 



As early as 1865, Cope began no fewer than five sep- 

 arate lines of research which he pursued concurrently 

 for the remainder of his career. On the fishes, he became 

 a high authority in the larger classification, owing to his 

 researches into their phylogeny, for which a knowledge 

 of extinct forms is imperative. On amphibia, he wrote 

 more voluminously than any other naturalist, discussing 

 not only the morphology but the paleontology and tax- 

 onomy as well. In this connection must be mentioned 

 not only Cope's exploration and collections in the Per- 

 mian of Ohio and Illinois, but especially the remains 

 from the Texas Permian, first received in 1877, upon 

 which some of his most brilliant results were based; 

 these of course included reptilian as well as amphibian 

 material. His third line of research, the Reptilia, is in 

 part included in the foregoing, but also embraced the 

 reptiles of the Bridger and other Tertiary deposits, those 

 of the Kansas Cretaceous, and the Cretaceous dinosaurs. 



Up to 1868 Leidy alone was engaged in research in the 

 West, but that year saw the simultaneous entrance of 

 Marsh and Cope into this new field of research, and their 

 exploration and descriptions of similar regions and forms 

 soon led to a rivalry which in turn developed into a most 

 unfortunate series of controversies, mainly over the sub- 

 ject of priority. This resulted in a permanent rupture 

 of friendship and the division of American workers into 

 two opposing camps to the detriment of the progress of 

 our science. This breach has now been happily healed, 

 and for a number of years the degree of mutual good will 

 and aid on the part of our workers has been of the high- 

 est sort. 



The extent of the western fossil area, and particularly 

 the explorations of three of Cope's aids, Wortman in the 

 Big Horn and Wasatch basins, Baldwin in the Puerco of 

 New Mexico, and Cummins in the Permian of Texas, gave 

 him so fruitful a field of endeavor that the occasion for 



