November 13 , 2016:

by Ben

Residing upon the wall of the Smithsonian’s Museum Support Center (MSC) in Suitland, Maryland is the skeleton of a giant prehistoric reptile. This is a cast of Rhomaleosaurus cramptoni, a short-necked plesiosaur from the early Jurassic rocks of England’s westeast coast. With broad jaws bristling with teeth and a length exceeding 22 feet, this specimen would surely be a crowd pleaser, and yet it has never been on display at the National Museum of Natural History. Since the MSC opened in 1983, only staff, visiting scientists, and gaggles of interns have seen it.

The original fossil from which the Smithsonian cast was taken came from an alunite mine on the Yorkshire coast. Miners unearthed the nearly complete Rhomaleosaurus in 1848. This was a year after Mary Anning‘s death, and plesiosaurs were already well known to British naturalists. The new specimen was uncommonly large, however, and the mine’s owner, George Augustus Phipps, displayed it with pride at his residence. Five years later, Phipps gifted the skeleton to his friend Phillip Crampton, an Irish anatomist. Crampton arranged for the plesiosaur to be displayed at the 1853 meeting of the British Association for the Advancement of Science, held in Dublin.

For nearly a decade, the skeleton remained in a semi-permanent tent that had been erected for the meeting. Eventually, increasing concern that the tent structure was not protecting the fossil from the elements led to the specimen’s conditional relocation to the Royal Dublin Society Museum. It was here that Alexander Carte and William Baily published the first – albeit brief – description of the Yorkshire plesiosaur, naming it Plesiosaurus cramptoni (Harry Seely moved it to the genus Rhomaleosaurus in 1874).

Around the same time that Carte and Baily were preparing their description, the Rhomaleosaurus received another fateful visitor. This was Henry Ward of Rochester, New York, founder of Ward’s Scientific Company. At the time, Ward was a well-known and well-regarded fossil and mineral dealer. Ward first traveled to Europe in 1854 at the age of 20. He continued to venture around the world collecting geological specimens, which he sold to fund his degree at the Paris School of Mines. Ward’s timing was excellent, and the connections he made during his studies put him in an ideal position to start a company supplying specimens to the new natural history museums that were springing up on both sides of the Atlantic. Ward was also permitted to take casts of museum specimens, apparently including the Rhomaleosaurus in Dublin.

Starting in 1866, the Ward Scientific Company catalog offered a plaster cast of “Plesiosaurus” cramptoni for sale. Described as the largest plesiosaur ever discovered, the fully painted cast was listed at $150, which would be a little over $4000 today. The skull or left fore-flipper could be had for $15 and $10, respectively.

Most of the Rhomaleosaurus casts are tucked away in geology departments or seminar rooms where they are not often seen by the public. The London copy is an exception, however. The Rhomaleosaurus holds court in the Fossil Marine Reptiles gallery, where it is the largest specimen on display. In fact, it may well be the second most-photographed object in the museum, after Dippy the Diplodocus. Somewhat anachronistically, the London Rhomaleosaurus is displayed with a placard about Mary Anning, even though it is one of the few specimens in the gallery she didn’t discover.

Sadly, the original Rhomaleosaurus fossils have not fared as well as the casts. In 1877, the Royal Dublin Society Museum was incorporated into the National Museum of Ireland, at which time the institution gained permanent ownership of the specimen. During a move in the 1920s, the Rhomaleosaurus was broken up with sledgehammers for ease of transport. Afterwards, the pieces were scattered throughout the collections for decades. Adam Smith has been instrumental in reuniting and restoring this historic skeleton (video of the pieces here). It was a principal subject of his 2007 doctoral thesis, and he oversaw the complete, three-dimensional preparation of the original skull. Currently, there are long-term plans to reassemble and display the Rhomaleosaurus at the National Museum of Ireland.

Smith, A. 2006. Dublin’s Jurassic “Sea-Dragon.” Geoscience 17: 26-27. http://plesiosauria.com/pdf/Smith_2006_Dublin_seadragon.pdf

Smith, A.S. 2007. Anatomy and Systematics of the Rhomaleosauridae (Sauropterygia: Plesiosauria). PhD thesis. School of Biology and Environmental Science, University College Dublin.

Smith, A.S. and Dyke, G.J. 2008. The skull of the giant predatory pliosaur Rhomaleosaurus cramptoni: implications for plesiosaur phylogenetics. Naturwissenschaften 95: 975-980.

Gilmore, C.W. 1941 A History of the Division of Vertebrate Paleontology in the United States National Museum. Proceedings of the United States National Museum 90.

Ward, H.A. 1866. Catalog of Casts and Fossils From the Principle Museums of Europe and America with Short Descriptions and Illustrations. Rochester, NY: Benton and Andrews.