Quarry 5 at the site. Later in 1884, Othniel Marsh named Diplodocus lacustris based on a chimeric partial dentary, snout, and several teeth collected by Lakes in 1877 at Morrison. In 2013, it was suggested that the dentary of D. lacustris and its teeth were actually from Apatosaurus ajax based on its proximity to the type braincase of A. ajax. All specimens currently considered Apatosaurus were from the Morrison Formation, the location of the excavations of Marsh and Cope. Second Dinosaur Rush and skull issue After the end of the Bone Wars, many major institutions in the eastern United States were inspired by the depictions and finds by Marsh and Cope to assemble their own dinosaur fossil collections. The competition to mount the first sauropod skeleton specifically was the most intense, with the American Museum of Natural History, Carnegie Museum of Natural History, and Field Museum of Natural History all sending expeditions to the west to find the most complete sauropod specimen, bring it back to the home institution, and mount it in their fossil halls. The American Museum of Natural History was the first to launch an expedition, finding a well preserved skeleton (AMNH 460), which is occasionally assigned to Apatosaurus, is considered nearly complete; only the head, feet, and sections of the tail are missing, and it was the first sauropod skeleton mounted. The specimen was found north of Medicine Bow, Wyoming, in 1898 by Walter Granger, and took the entire summer to extract. To complete the mount, sauropod feet that were discovered at the same quarry and a tail fashioned to appear as Marsh believed it shouldbut which had too few vertebraewere added. In addition, a sculpted model of what the museum thought the skull of this massive creature might look like was made. This was not a delicate skull like that of Diplodocuswhich was later found to be more accuratebut was based on "the biggest, thickest, strongest skull bones, lower jaws and tooth crowns from three different quarries". These skulls were likely those of Camarasaurus, the only other sauropod for which good skull material was known at the time. The mount construction was overseen by Adam Hermann, who failed to find Apatosaurus skulls. Hermann was forced to sculpt a stand-in skull by hand. Osborn said in a publication that the skull was "largely conjectural and based on that of Morosaurus" (now Camarasaurus). In 1903, Elmer Riggs