The articular ends are remarkable for their depressed oblong character, still preserving the anterior concavity with a small mesial process below, as in cervical vertebræ, and similar but smaller processes at the inferior outer angles of the posterior sub-semicylindrical convexity. The middle third of the anterior cup is made by the trapezoidal anterior end of the centrum; sometimes the sutures between it and the neural arch are well marked. The neural arch is large, commonly with a sub-circular neural canal. The neural spine is high, compressed so as to have the lateral surfaces sub-parallel and rounding into each other superiorly; and it has a less antero-posterior extent than the centrum. At its base behind it widens rapidly, and forms massive quadrate processes, extending outward and backward, which on the outside each have a flattened ovate zygapophysial facet, which also looks downward. Above the facet and separated from it by a groove is a tubercle. Between the zygapophyses behind the bone is concave from side to side; the facets are placed above the neural canal. The posterior zygapophyses are placed considerably higher than the anterior zygapophyses, and the part of the neural arch between is rather constricted from front to back. The neural arch steadily widens in front down to the base of the anterior zygapophysial processes in such way that the more or less flattened lateral surface looks outward and is gently concave from above downward. A ridge commencing at the tubercle over the posterior zygapophysial facet descends in a curve forward and downward, to form the posterior border of the anterior zygapophysial process. This is separated by a groove from the anterior articular surface, and anterior part of the base of the centrum, and has the aspect of a compressed part of the neural arch, extending obliquely downward, and forward, over and beyond the articular surface of the centrum. The anterior zygapophysial facets are oblong, narrow from side to side, and long from front to back; they are directed forward and a little outward, and are flattened, make nearly a right angle behind with the front of the neural arch, and look upward and inward. They are sometimes placed as high as the top of the neural canal, but are commonly lower. Around the neural canal the bone is conically impressed. Minute pneumatic foramina are in the usual position, between the centrum and the neural arch; and sometimes others behind the anterior zygapophysial process. The largest specimen known has the centrum nearly an inch and a half long.