_Vertebræ._ (Plates III., IV., V., VIII., XI.) The dorsal vertebræ are chiefly represented, in this series of bones, by three which are anchylosed together by their bodies and neural arches (Pl. V. figs. 1–5): the posterior articular surface of the body of the last of these vertebræ (ib., fig. 4, _c_) is subquadrate, longer in the vertical than the transverse direction, concave vertically, convex transversely, almost fitting, but being rather too small for, the anterior articular surface of the body of the first of the sacral series (Pl. VII. fig. 1, _c_). The difference is such as to indicate that only one dorsal vertebra may have intervened; and I conclude that the last of the three coalesced vertebræ is the penultimate dorsal. The anterior articular surface of the foremost of the three (Pl. IV. fig. 1, _c_) is 11 lines in transverse, and 4 to 5 lines in vertical diameter: it is concave transversely for the middle three-fifths, and convex transversely at the two outer fifths of its extent: it is more or less convex vertically throughout its extent. The bodies of these vertebræ are compressed and wedged-shaped, slightly expanded at their coalesced ends, produced below into subquadrate hypapophyses in the first and second (Pl. V. fig. 1, _hy_); while this process is restricted to the fore part (ib. _hy_ 3), or may be represented only by a slight anterior production of the lower edge of the wedge, in the third (ib. fig. 5, _hy_ 3). The hypapophysis of the first of the three expands at its termination (Pl. IV. fig. 1, _hy_), with the hinder angle bent back to coalesce with the front one of the next hypapophysis, which is somewhat longer, and bent forward with a similar terminal expansion: a full elliptical space is intercepted by this terminal confluence of these hypapophyses (Pl. V. figs. 1 & 5, _hy_). Each vertebra shows an elliptical articular cavity (ib. figs. 1 & 5, _p_, _p_ 3) for the head of the rib, near to the anterior articular surface; the long axis of this costal surface is directed from above obliquely downward and forward. The surface of the rib’s tubercle cuts obliquely the lower part of the free end of the diapophysis (Pl. IV. fig. 1, _d_).