Suborder THEROPODA

Family ORNITHOMIMIDAE

Omithomimus velox

Figure 6

Material. — YPM 542 cotype left distal end of tibia, metatarsals II-IV, phalanges I-1-3, YPM 548 cotype metacarpals I—III (Denver Formation, Loc. 35); DMNH 33300 manus claw (Denver Formation, Loc. 19); UCM 3539 phalanx (Denver Formation; Loc. 27); UCM 47633 distal caudal (Denver Formation, Loc. 27); and USGS D902 manus claw (Denver Formation?; Loc. 15).

Description and discussion. —The type material was briefly described by Marsh (1890; see also 1896a, 1896 b), with additional comments about the taxon by Osborn (1916), Russell (1972), and DeCourten and Russell (1985). As a whole, the limb material is proportionally more gracile than other ornithomimids such as Garudimimus or even Struthiomimus. Additional specimens, primarily unguals, have been found elsewhere in the Denver Basin, but only from the Denver Formation. DMNH 33300 is a nearly complete ungual, 40 mm long.