100 MEMOIRS OF THE CARNEGIE MUSEUM 
able length. The tubercular facet for the rib is of large size and concave in the 
antero-posterior direction. The transverse process is heavy, as is also the upper 
portion of the neural arch. ‘The pedicle and transverse processes are perforated 
by the canals referred to above. 
Ninth Dorsal Vertebra.—'The ninth dorsal is represented only by a portion of 
the neural spine, half of the neural arch, and the upper third of the centrum of 
NG 
Fic. 50. Lateral View of Sixth Fie. 51. Lateral View of Fia. 52, Lateral View of 
Dorsal of D. hollandi Peterson. }+ Seventh Dorsal of D. hollandi Eighth Dorsal of D. holland 
nat. size. Peterson. } nat. size. Peterson. } nat. size. 
the left side. The capitular and tubercular facets are only slightly smaller than in 
the preceding vertebrae. ‘The transverse process is of about the same size, but the 
perforations are somewhat smaller than in the eighth dorsal vertebra. 
Tenth, Eleventh, and Twelfth Dorsal Vertebrx. —The tenth, eleventh, and twelfth 
dorsal vertebree are represented only by fragments, but enough remains to supply 
essential characters. The centra are depressed and apparently have no ventral keels, 
and the neural spines still continue to have the median groove which extends from 
the base upward for some distance on the anterior face of the spines. On the tenth 
dorsal the rib-facets possess considerable size, but they rapidly diminish in the 
following vertebrae. The neural spines also show a rapid reduction, but the perfo- 
