Edward Cope's reconstruction of Laelaps aquilunguis. This work was on display in the original exhibition as item 11. Image source: Cope, Edward Drinker. "The fossil reptiles of New Jersey," in: American Naturalist, vol. 3 (1869), pp. 84-91, pl. 2.

Paper Dinosaurs 1824-1969

An Exhibition of Original Publications from the Collections of the Linda Hall Library

First U.S. Dinosaur Mount, 1902

Charles Beecher in 1901 completed the first skeletal restoration of a dinosaur to be mounted in the United States. The specimen, called at the time Claosaurus annectens, was one of two nearly complete skeletons that had been found in 1891 by John Bell Hatcher. O. C. Marsh had published a restoration in 1892, but he had not reconstructed the specimen, so after Marsh's death, Beecher took on the project of mounting the skeleton. The restoration was the first large panel mount ever attempted. It took advantage of the fact that the bones of this specimen retained their natural position with respect to each other.

It will be noticed that the dinosaur is in a running position, with the tail off the ground. At the time, this was unprecedented for ornithopod restorations, which always had the tail dragging on the ground, as seen, for example, in Dollo's restoration of Iguanodon

Beecher had a very practical justification for such a profound transformation; he explained that the left femur was shattered and could not be removed from the matrix, and since it was in a running position, the rest of the skeleton was mounted to conform to it. 

The second illustration shows a detail of the pelvis and hind limbs as they appear on the slab after restoration. But if the pose was chosen for pragmatic reasons, Beecher did defend the high tail; he pointed out that Iguanodon trackways had never revealed the presence of tail dragging, so it seemed reasonable to suppose that the tails cleared the ground.

The name Claosaurus was one of many names this specimen has worn over the years. For a more complete story, see "What's In a Name".

Pelvis and hind legs of the Claosaurus annectens mount. This work was on display in the original exhibition as item 26. Image source: Beecher, Charles E. "The reconstruction of a Cretaceous dinosaur, Claosaurus annectens Marsh," in: Transactions of the Connecticut Academy of Arts and Sciences, vol. 11 (1901-1902), pl. 43.

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Claosaurus annectens mount. This work was on display in the original exhibition as item 26. Image source: Beecher, Charles E. "The reconstruction of a Cretaceous dinosaur, Claosaurus annectens Marsh," in: Transactions of the Connecticut Academy of Arts and Sciences, vol. 11 (1901-1902), pl. 42.

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Marsh's Claosaurus, 1892

In 1891 Hatcher found an articulated skeleton, complete with skull, of an ornithopod. In 1892 Marsh named it Claosaurus annectens, and he illustrated his paper with this fine skeletal restoration. It shows the animal as an upright biped, a pose that had become standard for all of Marsh's restorations except for the large sauropods. After Marsh's death, Beecher would supervise the restoration of the actual skeleton for the Peabody Museum; it would be the first such skeleton in the United States.

Marsh's restoration of Claosaurus. This work is part of our History of Science Collection, but it was NOT included in the original exhibition. Image Source: Marsh, Othniel C. "Restorations of Claosaurus and Ceratosaurus," in: American Journal of Science, series 3, vol. 44 (1892), pl. 6.

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What's In a Name: The Trachodon Story

Trachodon mounts in the American Museum of Natural History. This work is part of our History of Science Collection, but it was NOT included in the original exhibition. Image source: Scientific American, July 23, 1910, vol. 103, no. 4, cover. 

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One of the real difficulties in consulting the primary sources on dinosaurs is dealing with changes in nomenclature. And probably no dinosaur is more confusing than the duck-billed dinosaur. This dinosaur appears many times in our exhibition, wearing a bewildering variety of names, such as Trachodon, Hadrosaurus, Thespesius, Diclonius, Claosaurus, Anatosaurus, Edmontosaurus, and Anatotitan. The following is a wishful attempt to sort this all out.

In the 1850s, Joseph Leidy created two dinosaur genera, based mainly on teeth. One was Trachodon, based on a tooth found out West (see item 9), and the other was Hadrosaurus, based on teeth and several limb bones found in New Jersey (see item 10). No skull was found in either location, so it was not yet known that these were duckbills.

In 1882, a nearly complete skeleton of an ornithopod dinosaur was found, complete with duck-billed skull, and it was named Diclonius mirabilis in 1883 by Edward Cope (see item 27). Cope never reconstructed the skeleton, and it was sold to the American Museum in 1899. Charles Knight made a sculpture of it in 1897, and a painting, and it was labeled (on Osborn’s advice) Hadrosaurus mirabilis.

Meanwhile, in 1892, Othniel Marsh described a similar specimen, found in 1891, and he called it Claosaurus annectens. This was mounted at the Peabody Museum at Yale in 1901, still as Claosaurus. Frederick Lucas, however, referred to this specimen in 1901 as Thespesius (see item 27).

In 1906, Barnum Brown excavated a duckbill skeleton in Montana, so now the American Museum had two skeletons (Brown’s, and Cope’s Diclonius, found in 1882). The Museum decided to mount both of them in 1908, and Brown called them, loosely, Trachodonts (see illustration on right).

In 1908, Charles Sternberg made the spectacular find of a duckbill mummy, and it was bought by the American Museum and placed on exhibit (see item 28). Both Sternberg and Osborn call it Trachodon. Trachodon is the name nearly all of these duckbills would subsequently wear until 1942.

In 1942, in a review of all the various hadrosaurs, two kinds of uncrested duckbills were recognized. Both were placed in the genus Anatosaurus. The Trachodon skeleton pair in the American Museum was renamed Anatosaurus copei, while the Trachodon mummy, and the Yale specimen (which were larger) were renamed Anatosaurus annectens. Thus matters stood for thirty more years.

In 1978, it was argued that Anatosaurus annectens was really too similar to an Edmontosaurus (discovered and named in 1917), and so it was renamed Edmontosaurus annectens. That is the current name of the Trachodon mummy and the Yale specimen.

Finally, in 1990, for various taxonomic reasons, Anatosaurus copei was renamed Anatotitan copei. That is the current name for the pair of Trachodon skeletons in the American Museum.

Does that clear everything up?