Coelosaurus, Leidy

Cope, E. D., 1869, Synopsis of the extinct Batrachia, Reptilia and Aves of North America, Transactions of the American Philosophical Society 11, pp. 1-252 : 119

COELOSAURUS, Leidy .

Another bird-like type of dinosaur, like Laelaps . The only species known is of more slender build and smaller size than the latter. The hollowness of its bones, etc., indicate its powers as a runner or leaper. But few remains of the genus have been procured. It is known only from one tibia. From this slight indication the degree of difference in general structure is not readily attainable. The tibia is in all its proportions more slender, and presents a higher crest; its distal articular surface is more transverse to its longitudinal axis. The species C. antiquus has been much smaller, and more lightly built; the tibia is about one-fifth the size of that of L. aquilunguis.