The (Almost) Definitive Camarasaurus, 1921
In 1902, the American Museum of Natural History had acquired Edward Cope's collection of fossil reptiles. Cope's descriptions and nomenclature were being generally eclipsed by the numerous and well-illustrated publications of Othniel C. Marsh.
To counter this trend, Henry F. Osborn and his colleagues at the American Museum published a detailed study of one Cope sauropod, Camarasaurus. Perhaps this dinosaur was chosen, not only because there was abundant fossil material in the Cope Collection, but because in consequence, Marsh's generic name of Morosaurus, which he had used for the type, could be replaced by Cope's Camarasaurus, which now had precedent.
This monograph has long been regarded by professionals as a landmark memoir, To the non-specialist, it is also very impressive, not just because of its sheer size (the pages are 36 x 27 cm.), but because of the wealth and variety of its visual images.
There are 127 illustrations in the text and 26 plates, many of them folding. Most of the line drawings were done by Rudolph Weber; the shaded wash drawings were the work of Erwin Christman, who also did the skeletal restorations.
The Christman paintings are incredibly fine; he must have been the most skillful artist who ever worked on dinosaurs. The drawings at left are some of the first to attempt to capture varying dinosaur expressions.
The figure reproduced below shows three photographs of a flat articulated cardboard model of Camarasaurus, in three different poses. The articulation allowed Christman to try out different stances before making his final restoration. The model itself must have been quite impressive; at 1/5 natural size, it would have been fully ten feet long.
Christman does Camarasaurus, 1921
In addition to his delicate drawings of a Camarasaurus head, and his construction of an articulated Camarasaurus skeleton, Erwin Christman contributed some other remarkable studies to Osborn's and Mook's 1921 monograph on Camarasaurus.
The plate reproduced at right shows four views of a model sculpture of the sauropod. And the illustration below shows an immense fold-out plate with a full skeletal restoration. Notice that the animal is tallest at the shoulders, rather than the hips. This misinterpretation would be corrected when the articulated Carnegie juvenile Camarasaurus was found the very next year (see next item).