OSTEOLOGY OF CARNIVOROUS DINOSAURS. 147 



touched upon. The discovery of more and better pteserved materials and the 

 description of specimens already in the collections of our museums will undoubtedly 

 add much to our knowledge of the skeletal modifications that have taken place 

 during successive geological periods. 



Such mechanical progression as has here been recorded is in the direction or 

 adaptation of the skeleton from the generalized to the specialized, thus producing a 

 more efficient mechanism for the particular purpose of speed and destructive power 

 so necessary for the maintenance of life itself. 



LIST OF WORKS CITED. 



Abel, O. Das Zeitalter der Reptilienherrschait. Vortrsige des Vereines zur Verbreitung naturwis- 

 senshaftlicher Kenntruise in Wein, vol. 49, 1909, pp. 9, 10, fig. 3. 



Beasley, Walter A. A Carnivorous Dinosaur; a reconstructed skeleton of a huge Saurian. Scien- 

 tific American, vol. 97, 1907, pp. 446-447, three text figures and cover (frontispiece). 



Cope, E. D. The Extinct Batrachia, Eeptilia and Aves of North America, Trans. Amer. Philos. Soc, 

 vol. 14, 1871, pp. 100-122. 



On the Skull of the Dinosaurian Laelaps incrassatus Cope. Proc. .\mer. Philos. Soc, vol. 



30, 1892, p. 241. 



On the homologies of the posterior cranial arches in the Reptilia. Trans. Amer. Philos. Soc, vol. 



17, 1892, p. 18. 



GiLMORE, Charles W. A New Rhynchocephalian Reptile from the Jurassic of Wyoming, with Notes 

 on the Fauna of "Quarry 9." Proc. U. S. Nat. Mus., vol. 37, 1910, pp. 39, 40, fig. 3. 



Osteolog)' of the Armored Dinosaiu-ia in the United States Museum, with Special Reference to 



the Genus Stegosaurus. Bull. 89, U. S. Nat. Mus., 1914,- p. 25. 



On the Fore Limb of AUosaurus fragilis. Proc. U. S. Nat. Mus., vol. 49, 1915, pp. 501-513. 



Hay, O. P. Bibliography and Catalogue of the Fossil Vertebrata of North America. Bull. 179, U". S. 



Geol. Surv. 1901, pp. 487-494. 



On Certain General and Species of Carnivorous Dinosaiu-s, with special Reference to Cerato- 



saurus nasicornis Marsh. Proc. U. S. Nat. Mus., vol. 35, 1908, pp. 351-366, text figs. 1-4. 



HuENE, F. VON. Die Dinosamier der Europaischen Triasformation, Geologische und paleontologishe 



abhandlungen Supplement, vol. 1, 1907-1908. Jena. 

 Hutchinson, H. N. Extinct Monsters. Ed. 2, 1893, pp. 83-85, figs. 16, 17, IS. 

 ■ Extinct Monsters and Creatures of other days. 1911, new edition, pp. 132-145, text figs. 42, 44, 



45, 46, pis. 14, 15. 

 Huxley, T. H. On the classification of the Dinosaurus, with Observations on the Dinosauria of the 



Trias. Quart. Jour. Geol. Soc. London, vol. 26, 1870, pp. 32 (with one plate). 

 Jaekel, Otto. Die Wirbeltiere, 1911, p. 160, fig. 176. 

 Lambe, L.M. On Dryptosaurus incrassatus (Cope), from the Edmonton Series of the Northwest 



Territory. Contr. Canadian Palaeont., vol. 3. pt. 3, 1904, pp. 5-27, pis. 1-8. 



On the Fore Limb of a Carnivorous Dinosaur from the Belly River Formation of Alberta, and a 



new genus of Ceratopsia from the same Horizon, with Remarks on the Integument of Some Cretaceous 

 Herbivorous Dinosaurs. Ottawa Naturalist, vol. 27, 1914, pp. 129-131, pi. 13. 



On a New Genus and Species of Carnivorous Dinosaiu' from the Belly River formation of Alberta, 



with a Description of the Skull of Stephanosaurus marginatus from the same Horizon. Ottawa Natur- 

 alist, vol. 28, 1914. pp. 13-17. 



The Cretaceous Theropodous JiinoaauT Gorgosaurus. Memoir 100, Geol. Surv. Canada, 1917, pp. 



1-84, 49 text figures. 

 Lucas, F. A. Animals of the Past. 1901, pp. 106, figs. 23, 25. 



Animals Before Man in North .\merica. 1902, pp. 164, figs. 



Lull, R. S. Dinosaurian Distribution. Amer. Journ. Sci., vol. 29, 1910, pp. 13-16, 19-21, figs, 1, 4, 8. 



The Reptilia of the Arundel formation. Maryland Geological Survey, Lower Cretaceous. 



1911, pp. 183-188. 



Cretaceous Dinosaurs. Bull. Geol. Soc. Amer., vol. 23, 1912, pp. 208, 209. 



