DEINODONTIDAE Cope, 1866

Gilmore, Charles W., 1946, A new carnivorous dinosaur from the Lance Formation of Montana, Smithsonian Miscellaneous Collections 106, pp. 1-19 : 2

Family DEINODONTIDAE Cope

The Deinodontidae includes all of the large Upper Cretaceous carnivorous dinosaurs such as Deinodon , Tyrannosaurus , Gorgosaurus , and Albertosaurus . The affinities of the present specimen appear to be in the genus Gorgosaurus , as shown by many close similarities to G. libratus and G. sternbergi , thus greatly extending the geologic range of Gorgosaurus from the Belly River into the Lance. On the basis of its geologic occurrence, smaller size, and slight differences in skull structure, it becomes necessary to describe it as a new species, for which the name G. lancensis is proposed. The specific name is in reference to the Lance formation in which the type specimen was found.

Although following Matthew and Brown (1922) in their conception of the availability and scope of the family Deinodontidae , it is well to point out that the genotype, Deinodon horridus , was founded by Leidy (1856) exclusively upon detached teeth, a fact well known to both of the above authorities, but who make the dogmatic statement that the family Deinodontidae was "based upon an unquestionably valid genus." With this conclusion I disagree for, with the accumulating evidence of later years, it becomes more and more apparent that genera of Upper Cretaceous carnivorous Dinosauria cannot be differentiated on tooth characters alone. It therefore appears highly probable that the use of the genus Deinodon may have to be abandoned and with it, following nomenclatural procedure, the family term Deinodontidae .