22a. The Complete Carnegie Quarry Map, 1901
This is believed to be the earliest known quarry map of a dinosaur excavation. Two Diplodocus specimens are mapped here; when excavated, these two specimens made up the composite Diplodocus carnegiei that was mounted at the Carnegie Museum of Natural History in 1901.
Hatcher, John Bell. "Diplodocus (Marsh): Its osteology, taxonomy, and probable habits, with a restoration of the skeleton," in: Memoirs of the Carnegie Museum, vol. 1 (1901), pp. 1-63. This work was on display in the original exhibition as item 22.