In 1858 the world’s most complete dinosaur skeleton was found in a clay pit outside of Philadelphia. For the first time, enough bones were found from a single animal for scientists to get a fairly accurate idea of how a dinosaur actually looked. As early as 1838, large fossilized bones began turning up in the marl pits on Birdwood farm in Haddonfield, NJ. Since the late 1700’s, marl (a calcium rich clay formed in aquatic environments) had been collected and used as fertilizer. The bones were originally treated as a novelty and given away as doorstops and umbrella stands.
In 1858 William Foulke, a member of Philadelphia’s Academy of Natural Sciences, was dining at Birdwood farm when he heard about the bones, and promptly began a new excavation. It was this excavation that yielded 35 bones – the most complete dinosaur skeleton ever found. The bones on this mount are casts of the originals which are housed in Philadelphia’s Academy of Natural Science’s research collection.
Foulke turned the bones over to Joseph Leidy, his boss at the Academy, specialist in anatomy/physiology, and one of the foremost experts on American dinosaurs. It was Leidy who named the dinosaur after its discoverer, and who sketched an anatomical drawing of the animal. When the reconstructed Hadrosaurus went on display at the Academy in 1868, it was the world’s first mounted dinosaur skeleton – as well as the first depicted on 2 legs instead of 4.
Prior to this, dinosaurs had been portrayed as heavy, bulky animals similar to iguanas or crocodiles, as can be seen in the 1854 Crystal Palace dinosaurs from London:
In fact, it was their British sculptor, Benjamin Waterhouse Hawkins, who came to Philly to design and cast the skeleton.
The Academy’s historical artifacts are not always on exhibit, but I was once lucky to see some of the artifacts exploring the Academy’s influence on the field of paleontology – these highlighted Leidy, as well as Philadelphian/Academy member Edward Drinker Cope and his infamous “bone wars” with Yale’s OC Marsh.
The Academy still has an active paleontology program. In 2004 Academy paleontologist Ted Daescher discovered the fossilized remains of a fish with limb-like fins.
In the back of the dinosaur gallery, visitors can often view (and talk to) staff working on fossil preservation:
Today, the Hadrosaurus find is commemorated not only as New Jersey’s state dinosaur, but with a statue in downtown Haddonfield.
You can also visit a mini-park in Haddonfield commemorating the site of the original excavation (and play with a few dinosaurs!).
Trivia: along with the Hadrosaurus bones, the Academy also houses Thomas Jefferson’s fossil collection, including a mastodon jaw collected by William Clark (one goal of the Lewis & Clark expedition was to find evidence to disprove a popular European theory on the degeneracy of American species).
Another fossil-rich marl pit in South Jersey has been purchased by Rowen University as the center-piece of their paleontology department, and will eventually be turned into a public fossil park. In the meantime, they offer public tours/fossil collecting a few times/year. https://www.rowan.edu/fossils/
To collect your own fossils, visit Big Brook (Collecting Shark’s Teeth and Other Fossils in New Jersey).