10 
Donald Baird and John R. Horner 
forms a symmetrical arch. The proximal end bears a pair of shallow con- 
cavities for the reception of the distal condyles of a preceding phalanx, 
whereas if this were the first phalanx it would be singly concave to receive 
the single condyle of the metatarsal. Thus the Phoebus Landing specimen 
probably represents the second phalanx of the third digit. It closely 
resembles phalanx III-2 of all the ornithomimids, including AMNH 2551 
from Monmouth County, New Jersey. 
The earliest name for an ornithomimid from the Atlantic coastal 
deposits is Coelosaurus antiquus Leidy, 1865, based on a well-preserved tibia 
(ANSP 9222) from the greensand of Burlington County, New Jersey. 
However, Leidy ’s generic name proves to be a junior homonym of 
Coelosaurus [Owen] 1854 (see Appendix). We accordingly transfer the 
species antiquus to the oldest junior subjective synonym of Coelosaurus 
Leidy, which is Marsh’s genus Ormthomimus. Fragmentary remains in- 
distinguishable from Ormthomimus are found from the late Santonian or 
early Campanian through the late Maestrichtian of New Jersey and 
Delaware (Baird and Horner 1977). As the Phoebus Landing assemblage 
is Campanian in age and belongs to the same faunal province as those of 
New Jersey and Delaware, we concur with Miller’s provisional assign- 
ment of the North Carolina specimen to Ormthomimus . 
Suborder SAUROPODOMORPHA 
Infraorder SAUROPODA 
Family incerta 
Hypsibema Cope, 1869 
Neosaurus Gilmore in Gilmore and Stewart, 1945; non Nopcsa, 1923. 
Parrosaurus Gilmore, 1945 (replacement name). 
Hypsibema eras sic auda Cope 
Hypsibema crassicauda Cope, 1869: 192; 1870: 122-G — 122-1 ( partim ), PI. 
1, Figs. 15-1 5 A- 1 5 B ; 1871: 211-214 ( partim ); 1875: 36-40 {partim ), PI. 
5, Figs. 2-2a-2b, PI. 6, Fig. 3 (only). Type species by monotypy. 
Figs. 4A-A 1 , 5, 6 
Type. — USNM 7189, a syntypic suite of mixed generic origin. We 
designate as lectotype the caudal vertebra illustrated by Cope (our Figs. 
4A-A 1 , 5A), collected by W. C. Kerr from James King’s marl pits in 
Sampson County. 
Hypodigm. — The lectotype and the following caudal vertebrae from 
Phoebus Landing, Bladen County: USNM 6136, Berry and Stephenson 
coll., 1907, cited erroneously as cotype by Lull and Wright (1942: 224) 
