The foramina enclosed by the transverse processes are large; and have, on the internal side, their long diameter obliquely transverse to the axis of the sacrum. The inferior faces of the centra are slightly concave in the first three. The first and fourth have slight hypophysial keels. The neural canal is very wide and depressed in the first, but decreases rapidly backwards, becoming extremely small in the last. _Caudal region_ (Plate VI., Fig. 6).--(Description based upon the first four.) The centra of the caudal vertebræ are rather long, narrow, and greatly depressed in the middle; they decrease in size gradually backward. The pedicles and laminæ are short and thin, enclosing a small neural canal. The neural spines point directly back, being almost parallel with the axis of the centrum. They are slender and tuberous at the extremity. The transverse processes are very long, wide, and thin, thickened somewhat at the ends, and project directly out; they decrease in size backwards. From the persistence of the neural canal, and from its comparative size, it would seem as if the tail was considerably larger than that of the elephant. _Measurements of Vertebræ._ _Cervical region_ (Plate VI., Fig. 11). M. Diameter of cervical (vertical) ·079 Diameter of cervical (transverse) ·111 Diameter of cervical (fore-and-aft) ·051 Extreme length of prolongation of pedicles for zygapophyses ·089 Long diameter of vertebraterial canal ·040 Width of pedicles ·035 _Dorsal region_ (Plate VI., Figs. 2 and 3). M. In anterior region: Diameter of centrum (fore-and-aft) ·075 Diameter of centrum (vertical) ·062 Diameter of centrum (transverse) ·142 In posterior region (Plate VI., Fig. 3).: Diameter of last dorsal (vertical) ·087 Diameter of last dorsal (transverse) ·110 Average width throughout the series of neural canal ·097 Width of transverse process (anterior dorsal) (Fig. 2, Plate VI.) ·075 Length of lamina from prezygs. to post-prezygs. (Fig. 2, Plate VI.) ·12 Length of transverse process (middle dorsal). (Fig. 3, Plate VI.) ·055 Vertical length of anterior dorsal from tip of spine to hypapophysial keel ·183 Width between inner margins of metapophyses (last dorsal) ·172 _Lumbar region_--Last lumbar (Plate VI., Figs. 4 and 5).