ONE OF THE BEST DESCRIPTIONS OF ANY TYRANNOSAURID FIRST EDITION, 7 engraved folding plates, 4 heliotypes, 38 text illustrations, original grey printed wrappers, ink stamps of the Geological Society of London to the upper wrapper and title, ownership stamp of William P. Ogilvie to the upper wrapper, spine slightly toned, hinges reinforced with tape, 8vo, Ottawa, Government Printing Bureau, 1917 First edition of this important and copiously illustrated monograph that was one of the first publications to illustrate a dinosaur in non-standing positions. Canadian palaeontologist, Lawrence Lambe, “was one of the first dinosaur hunters to discover the richness of the Red Deer River beds in Alberta around the turn of the century, but he was not an avid field worker, and he moved on to become Chief Paleontologist for the Geological Survey of Canada.” (Paper Dinosaurs) His published work, describing the diverse and plentiful dinosaur discoveries from the fossil beds in Alberta, did much to bring dinosaurs into the public eye and helped usher in the Golden Age of Dinosaurs. Gorgosaurus libratus (now Albertosaurus) was first described by Lambe in 1914, from a well-preserved skeleton from today’s Dinosaur Provincial Park. He followed it up in 1917 with this work, considered one of the best descriptions of any tyrannosaurid. Lambe supplemented his thorough description with photographs of the field excavation, a drawing of the fossil as found, and a full skeletal restoration. However, the most innovative part of this work is a set of four very faint pen drawings showing the life of Gorgosaurus in standing, sitting, feeding and lying positions. The drawings, done by Arthur Miles under Lambe’s direction, were among the first to show a dinosaur in positions other than the standard standing posture. Additional species of Albertosaurus and Gorgosaurus were described by Parks (1928) and Gilmore (1946). A very good copy of a scarce work, important in the history of dinosaurs. Provenance: Geological Society of London William P. Ogilvie [A New Carnivorous Dinosaur from the Lance Formation of Montana, Gilmore, 1946; Paper Dinosaurs 36, Ashworth]