384 OSBORX AXD MOOK SAUROPODS OF COPE 



red series apparently having come from a different quarry than those 

 of the yellow series. The red bones probably came from Cope Quarry 

 Xo. 1, and the yellow from Cope Quarry Xo. 2. The limitations of color 

 in determining the original association of bones have been indicated 

 above. The bones of the earlier collection were given the niimber 5760, 

 with variations according to their identification as individuals, such as 

 5160' and 5760'', and probably were mostly from Quarry Xo. 1; the bones 

 of the later collection were given the base number 5761, with a further 

 modification into 5T61-a for a presumably different individual than the 

 rest of 5761, and were probably from Quarry Xo. 2. 



In connection with this work, which was carried on in 1904, Mr. Eu- 

 dolph AVeber, then artist of the Department of Vertebrate Paleontology, 

 made line drawings of many of the vertebra. In 1906 some wash draw- 

 ings of the skull material were made by Mr. Erwin S. Christman. These 

 illustrations were originally prepared for the United States Geological 

 Survey Monograph on the Sauropoda, in course of preparation by Pro- 

 fessor Osborn. The cost of preparation of these drawings was borne by 

 the Survey. 



RESEARCH IX 1912-1919 



In 1912 work on the Cope Opisthocoelia material was renewed as part 

 of the preparation of the Sauropoda Monograph, which was being pre- 

 pared for the Survey by Professor Osborn. This work was undertaken 

 I)y the present junior author under the direction of the senior author. 

 The entire Cope Collection of Opisthocoelia from Canyon City was studied, 

 among other material, with the object of separating the vertebra? and limb 

 bones referable to Camarasaurus, Ampliiccelia.s, and the other Cope genera 

 and arranging them in series similar in size, proportion, and color, as well 

 as determining the characters of Camarasaurus and Ampliiccelias and the 

 less knovm genera. To a considerable extent this work consisted in veri- 

 fication of the previous work by Doctor Matthew and Doctor Gregory, in 

 modification of their results, in a few cases, and in expanding them to 

 meet the present needs. 



■ This research has terminated in the arrangement of the vertebra? and 

 ribs in morphological series, which may represent originally distinct indi- 

 viduals or they may not. The attempt was made to associate the bones 

 of single individuals so far as practicable, but in many cases evidence for 

 this was insufficient and in such cases an effort was made to assemble 

 series that would be reasonably constituted in a morphological sense. The 

 arrangement of the bones in these series is as accurate as it could be made, 

 in view of the distorted, sometimes incomplete, and badly mixed character 



