

Othniel Chcwles Marsh. 4:1^1 



His work on the Peptilia is not equally divided among the 

 various orders, for the Dinosauria claimed his attention above 

 all others. To this group he lent his best efforts, and he com- 

 passed it so thoroughly as to be its sole master. It seems only 

 necessary in this place to notice the complete restorations he 

 made of some of these remarkable animals. In this list are 

 included Anchisaurus, Brontosaurus, Zaosaurus, Cerato- 

 sauruS) Camptosaurus, Stegosaurus, Triceixito-ps, and Olao- 

 saurus. It must be remembered that nearly all these animals 

 were of gigantic stature, some of them the largest land 

 animals yet known, and also that each restoration represents a 

 number of separate investigations on the structure of the skull, 

 the limbs, the vertebrse, the pelvis, etc. In most cases, only by 

 this means was it possible to bring together gradually, part by 

 part, until the sum of the knowledge warranted a complete 

 representation of the skeleton. The material of many of the 

 genera he described is still in these various stages of progress, 

 awaiting new additions of portions yet unknown in order to 

 form a finished conception of the entire animal. His exten- 

 sive report on the Dinosaurs of North America, published in 

 1896, gave a synopsis of what he had accomplished up to that 

 time, but as remarked elsewhere their philosophical treatment 

 he had reserved for his final monographs. 



Probably, among the Reptilia, next in importance to his 

 work on the Dinosauria is that on the Mosasaurs. In this he 

 first announced the discovery of the dermal armor, the position 

 of the quadrate, the finding of the stapes, the columella, the 

 hyoid, the sclerotic plates, the quadrato-parietal arch, the malar 

 arch, the transverse bone, the pterygoids, the pterotic bone, 

 the sternum, the anterior limbs, the posterior limbs, the length 

 of the neck, and details of the pelvic region. Thus he con- 

 tributed a knowledge of some of the most essential characters 

 of the skeleton in this group. In other groups of aquatic rep- 

 tiles, he also brought out new genera and types of structure. 

 Prominent among these may be mentioned Baptanodon, a 

 toothless Ichthyosaurian. Marsh was the first to describe the 

 remains of fossil serpents in the western Tertiary deposits, and 

 likewise the first to discover the remains of* flying reptiles in 

 America. The latter were of unusually large size and remark- 

 able for the absence of teeth. 



