From Today In Science History:
O.C. Marsh (October 29, 1931 - March 18, 1899)
In 1866, the Peabody Museum of Natural History was founded with a gift from George Peabody. The same year his nephew, O.C. Marsh, was also named its Professor of Paleontology, the first such appointment in the United States. In 1869 Marsh used the inheritance from his uncle to start to amass large collections of vertebrate fossils. He went on to long and successful career as a vertebrate paleontologist, most of which was spent fueding with is rival, E.D.Cope.
Marsh and Cope started their careers on a cordial basis, but the relationship soon soured over an incident involving Cope's fossil of Elasmosaurus. Embarassingly, Marsh pointed out that its backbones were mounted backwards. To settle the arguement the men agreed to let Joseph Leidy decide who was right. Leidy promptly removed the head from one end and placed it on what Cope had thought was the tail. Cope than frantically tried to collect all of the copies of a recently printed publication that contained his erroneous reconstruction.