Dusting Off America’s First Dinosaur


During the summer of 1858 almost no one in the United States had even heard of dinosaurs. The term itself was only seventeen years old, having been coined by Sir Richard Owen in 1841 to describe a few scattered bones and teeth found in England some two decades before. Several colossal models had been built on the grounds of the Crystal Palace at Sydenham, England, but even with Owen’s expertise they bore little resemblance to the iguanodons and megalosaurs they were supposed to portray. The problem was that remains of dinosaurs had been found in only the most fragmentary condition. And nothing approaching a dinosaur skeleton had been unearthed anywhere in the world.

One of the few Americans who had heard of dinosaurs was Dr. Joseph Leidy, a professor of anatomy at the University of Pennsylvania, a member of the Academy of Natural Sciences in Philadelphia, and the country’s foremost vertebrate paleontologist. By 1858 various scientific expeditions traversing the Western wilderness had gleaned enough information about great fossil beds to suggest to him that dinosaurs would be found there soon. Nevertheless, when the great discovery came, it would be from a most unexpected direction.

It so happened that William Parker Foulke, a member of the academy, was summering in Haddonfield, a small, pleasant town some five miles from Philadelphia, across the river in New Jersey. There Foulke learned of an incident that had taken place some twenty years before. One of Foulke’s neighbors, a well-to-do farmer named John Hopkins, had been digging marl (a kind of clay rich in phosphates and widely used as a fertilizer) from a deep stream bed near his house when the workmen uncovered a quantity of huge bones. Hopkins no longer had any of the fossils, but Foulke talked him into renewed digging.

Finding the site proved unexpectedly difficult. The marl pit had become choked with eroded debris from the banks and so overgrown as to be virtually indistinguishable. Hopkins himself was no longer sure of the precise location. One of the original workmen who had discovered the bones was summoned, pondered a bit, and pinpointed a spot—which turned out to be wrong. Nevertheless, on the second day of searching, the old pit was discovered and excavation began in earnest.

At a depth of ten feet, the searchers found what they were looking for, a jumble of large black bones heavily impregnated with iron. There was most of the left side of a skeleton, including part of the hip and nearly all of the fore and hind limb, in addition to twenty-eight vertebrae and nine teeth—but no skull. Since the bones in many cases showed signs of fracture, great care was taken in removing them. After sketching and measuring, each was placed on a board, wrapped in cloth, and gingerly transported by straw-filled cart three-quarters of a mile to Foulke’s residence.


Leidy was notified of the find and soon arrived on the scene. At his instigation, digging continued intermittently through the end of October, but little else of value was uncovered. Nevertheless, America had its first dinosaur and the world its first dinosaur skeleton. Leidy promptly christened it Hadrosaurus foulkii in honor of his colleague. (Hadrosaurus means “bulky lizard.”)

The bones were officially presented to the academy in December, and Leidy used the occasion to unveil the results of his study of the specimen. He noted that the bones were those of a “huge herbivorous saurian...closely allied to the great extinct Iguanodon of the Wealden and Lower Greensand deposits of Europe.” No surprise here; this much was clearly indicated by the lozenge-shaped teeth. But Leidy had also been particularly struck by the disproportion between the front and hind limbs. This suggested that the animal had assumed an upright posture, at least while browsing, “sustaining itself, kangaroo-like, in an erect position on its back extremities and tail.” Leidy was the first person to get dinosaurs off all fours.

The kangaroo simile evidently left a lasting impression. For a quarter-century or more, Hadrosaurus was repeatedly billed as the “Great Kangaroo Lizard,” even by such prestigious institutions as the Smithsonian. Unfortunately this recurring image also helped foster a popular misconception that dinosaurs actually hopped about with gigantic bounds; as late as 1912 Sir Arthur Conan Doyle so portrayed them in his science fiction classic The Lost World.

All this was far in the future, however. Leidy ended his talk with some observations on the creature’s habits. He envisioned Hadrosaurus following a semiaquatic existence in tidal waters, subsisting mostly on conifers. Flowering plants were just beginning to put in an appearance in the Cretaceous world of a hundred million years ago.