A NEW PTEROSAURIAN REPTILE FROM THE MARINE 

 CRETACEOUS OF OREGON 



By Charles W. Gilmore 

 Curator of Verteln-ate Paleontology, United States National Museum 



Through the kindness of Prof. E. L. Packard, of the University 

 of Oregon, I have recently received for study a fossil specimen found 

 by him in the marine Cretaceous rocks of eastern Oregon. This 

 specimen clearly belongs to the Pterosauria, and, as this reptilian 

 group has not previously been known to occur in the Pacific coast 

 region of North America, the discovery is of much scientific interest. 



In North America pterosaurian remains have been found in the 

 marine Niobrara Chalk of -western Kansas and in the fresh-water 

 Morrison deposits of Wyoming. Three genera are recognized — 

 Pteranodon and Nyctodactylus from the Niobrara, and Dermodacty- 

 lus from the Morrison formation. The first two mentioned genera 

 are adequately defined from well-preserved specimens ; but the latter, 

 founded on a single incomplete and poorly preserved skeleton, is at 

 this time inadequately characterized. 



Well-preserved pterosaurian specimens are among the rarest of 

 American reptilian fossils, and when this pterosaurian fauna is con- 

 trasted with those of Great Britain and Europe, with their great 

 number of genera and species of wide geological range, the paucity 

 of our rocks in pteryodactyle remains becomes strikingly apparent. 

 This comparison serves also to accentuate the importance of this latest 

 discovery, in greatly extending their Imown geographical range as 

 well as furnishing a representative of the order that is intermediate 

 in geological position between the earliest and latest known American 

 members. 



In regard to the geological occurrence of this specimen. Professor 

 Packard, under date of September 19, 1927, writes me as follows: 

 "These specimens were found in Cretaceous shales associated with a 

 determinable ammonite fauna of Lower Chico, or possibly Upper 

 Horsetown age." The specimens referred to in the above citation are 

 the pterosaur and an ichthyosaur,^ the first and only vertebrate re- 

 mains so far found in this formation. 



iMerriam, J. C, and Gilmore, C. W., Carnegie Instit. of Washington. Pub. No. 393, 

 1928, pp. 1-4. 



No. 2745.— Proceedings U. S. National Museum. Vol. 73, Art. 24 



97555—28 1 



