Dryptosaurus aquilunguis, Cope, 1866

Russell, Dale A., 1970, Tyrannosaurs from the Late Cretaceous of western Canada, Ottawa: National Museum of Natural Sciences, Publications in Palaeontology, No. 1 : 3

Gilmore (1946: 17) considered Dryptosaurus aquilunguis from the late Cretaceous of New Jersey to be closely related to the large theropods of similar age in the interior of North America and suggested that the family group name ' Dryptosauridae' ( Marsh 1890: 424) would be available for them should Deinodontidae prove to be based on an indeterminate type genus. In Dryptosaurus (for descriptions and measurements see Cope 1869 -70: 100-08; Huene 1932: 63-4) the manus is larger than in any known tyrannosaur. The ungual phalanx of the first digit is very large, the length of its convex upper surface amounting to 75 per cent of the total length of the humerus. In Daspletosaurus , where the manus is relatively large for a tyrannosaur, this length is approximately equal to only 40 per cent of the length of the humerus. The femur in Dryptosaurus is very slender, and in contrast to conditions in a half-grown tyrannosaur where the circumference / length ratio of the femur is comparable ( AMNH 5423 ), the tibia is distinctly shorter than the femur. It is unlikely that additional material of Dryptosaurus will show that this genus and the western forms should be placed in the same family.