Sauropods in the American West, 1883
The discovery of the Bernissart iguanodons, coupled with earlier evidence provided by Hadrosaurus and Compsognathus, was pushing the paleontological world to tip all dinosaurs up onto their hind legs like gigantic birds. But at this very moment, intrepid explorers in the western United States were finding indisputable evidence of gigantic dinosaurs that must have stood firmly on all four feet. They were quickly labelled as sauropods, since they stood like lizards. The classic specimen of this new kind of dinosaur was Brontosaurus.
A nearly complete Brontosaurus skeleton was found in Lake Como, Wyoming, in 1879, by parties under the direction of Othniel C. Marsh. Marsh published a full skeletal restoration in 1883.
Unfortunately, the skeleton lacked a head when found, so Marsh added a skull that was modelled on one found quite some distance away.
We now know that the skull Marsh used belonged to a Camarasaurus, which is quite a bit shorter and wider than the proper skull (see detail at right). Marsh neglected to mention in the text that the restored skull was conjectural; later restorations continued to adopt the Camarasaurus-like skull for nearly a century (see item 41).
In 1877, Marsh had found the bones of another large sauropod, which he had named Apatosaurus. Apatosaurus and Brontosaurus are now recognized to be synonyms, so the later name Brontosaurus is no longer scientifically valid, although it remains in public use.
Marsh's Unpublished Brontosaurus Restoration, 1966
In his various papers in the American Journal of Science, Marsh continually mentioned that his published illustrations, usually wood engravings, were reduced versions of larger plates prepared for the United States Geological Survey to accompany a monographs in preparation. These larger plates were actually prepared as lithographs, but they were never published. At least not until 1966, when John Ostrom and John McIntosh performed the singular service of finally seeing the hundred and fifty original plates through the press. The authors say in the preface that the plates were prepared under Marsh's direction by illustrator F. Berger and lithographer E. Crisand; the USGS bore the cost of $45,000.
All of the plates are impressive, but the most eye-catching is the Brontosaurus, which in this fold-out is about three times as big as Marsh's published versions of 1883 and 1896.