Cretaceous Dinosaurs 
21 
badly damaged vertebra of Hypsibema. Two additional caudals from 
Phoebus Landing, USNM 7094 and 7095, were assigned to Hadrosaurus 
tripos by Lull and Wright; the second is correctly identified (i.e. is ceta- 
cean) but USNM 7094 is here transferred to Hypsibema crassicauda. Thus 
USNM 7190, the vertebra upon which Cope’s species concept was prin- 
cipally based, remains as the lectotype of Hadrosaurus tripos. 
Locality and age . — W.J., Thompson’s marl pit in Sampson County, about 
10 miles (16 km) from James King’s marl pit; collected by W. C. Kerr. 
Cope’s original announcement of fossil reptiles from North Carolina 
began with the curious statement that the remains were “of cretaceous 
age, which were Intrusive in miocene beds.” As noted above, the actual 
stratigraphic relationship is one of residual patches and erosional residue 
of Tertiary marls overlying a Cretaceous terrane. Its zoological affinities 
indicate that the type specimen of H. tripos (with other misidentified ceta- 
cean bones from the “Cretaceous”) must have been derived from the 
Duplin Marl. According to the Geological Society of America’s correla- 
tion chart (Cooke et al. 1943) the Duplin is a lateral equivalent of the up- 
per part of the Yorktown Formation. Its age is there indicated as latest 
Miocene, but more recent investigation points to a Pliocene dating (Baum 
and Wheeler 1977). 
Discussion . — As Cope did, we have compared the type specimen of 
Hadrosaurus tripos with the caudal vertebrae of the type species, H. foulku 
Leidy\(type, ANSP 10005) — as well as those of numerous other 
dinosaurian genera — but we cannot concur with his identification. In its 
morphology, and particularly in the presence of zones of coalescence be- 
tween the epiphyses and the body of the centrum, the vertebra is clearly 
mammalian and evidently cetacean. This reinterpretation was confirmed 
independently by Clayton E. Ray and Frank C. Whitmore, Jr. (pers. 
comm., 1977), who identified the specimen as a caudal vertebra of a 
balaenopterine whale and noted that its size is appropriate to Megaptera 
expansa Cope, 1868. The latter species, however, was rejected by Kellogg 
(1968: 116-118) on the grounds that Cope’s syntypic series is a mixture of 
generically indeterminate vertebrae of two taxa from three localities in 
Maryland and Virginia. Surely the nominal species Hadrosaurus tripos has 
no greater claim to taxonomic validity than Megaptera expansa ; and while 
it must be removed from the genus Hadrosaurus , we feel that there is no 
genus of whale to which it can be justifiably transferred. We list it 
therefore as “Hadrosaurus tripos ” Cope, nomen dubium. 
The large vertebral centrum (SM 13025) from Phoebus Landing ten- 
tatively assigned to Protamia by Miller (1968: 470, PI. 1, Figs. 1, 3) was 
shown by Boreske (1974: 75, Fig. 26H) to be a cetacean caudal. Like the 
