NO. 14 A NEW SAUROPOD DINOSAUR GILMORE 7 



other bones ^; Monoclonius sp., horn core and fragments of f rilP ; 

 armored dinosaur suggesting a Belly River genus/ humerus ; a car- 

 nivorous form suggesting Dryptosaiirus or Dynamosaurus, dentary ■* ; 

 undeterminable fragments of other trachodont, ceratopsian, and car- 

 nivorous dinosaurs ; turtle and crocodile bones. 



In 1910 the late Dr. S. W. Williston ° reported the discovery of 

 a Sauropod coracoid in the Trinity Sand of Oklahoma, Lower Creta- 

 ceous in age, which, in so far as western North America is concerned, 

 represented the latest occurrence of Sauropod dinosaurs, up to the 

 time of the present discovery. In the eastern United States, Sauro- 

 pod dinosaurs {Astrodon, Plcurocoelns) have been known as occur- 

 ring in the Arundel (Potomac) formation since Marsh first described 

 them in 1888, but for a long time the Arundel was correlated with 

 the Morrison formation (Atlantosaurus beds) of the west, but more 

 recently, largely on paleobotanical evidence, it has been referred to 

 the Lower Cretaceous. A recent restudy of the Arundel vertebrates ° 

 appears to indicate a higher position in the Lower Cretaceous than 

 has previously been given them. It is also of interest that the Mary- 

 land Sauropoda are found associated with the remains of other dino- 

 saurs having undoubted Upper Cretaceous affinities, as is the case with 

 the bones now under discussion. 



It thus appears that these specimens, found under conditions which 

 allow no question of doubt to be raised, furnish the first indisputable 

 evidence of the occurrence of Sauropodous dinosaurs in the Upper 

 Cretaceous of North America. 



REPORTED DISCOVERIES OF SAUROPOD REMAINS IN UPPER 

 CRETACEOUS DEPOSITS 



There have been a considerable number of reported occurrences of 

 Sauropod dinosaur remains in Upper Cretaceous deposits in various 

 parts of the world. Those recorded are from India, southern France, 

 South America, Madagascar, German East Africa, and Egypt. These 



^ Brown, Barnum, The Cretaceous Ojo Alamo beds of New Mexico, with 

 description of the new dinosaur genus Kritosaurus : Am. Mus. Nat. Hist. 

 Bull., vol. 28, p. 269, 1910. 



Gilmore, C. W., Vertebrate faunas of the Ojo Alamo, Kirtland, and Fruit- 

 land formations, U. S. Geol. Surv. Prof. Paper No. 98, pp. 283-284, fig. 28; 

 p. 285, 1916. 



^ Brown, Barnum, idem, p. 278. 



^ Gilmore, C. W., idem, p. 287. 



■* Gilmore, C. W., idem, p. 288, pi. y^^ fig. i. 



^ See Larkin, Pierce, Journ. Geol., vol. 18, No. i, 1910, p. 93. 



■^ Gilmore, C. W., Proc. U. S. Nat. Mus., vol. 59, 1921, pp. 581-594, pis. 110-114. 



