166 ODONTORNITHES. 



The neural canal is of moderate size in this vertebra, and from its 

 walls a pair of well developed pre-zygapophyses project forward. They 

 extend in front of the end of the centrum by nearly half their length, and 

 bear at the end small subcircular facets for articulation with the preceding 

 vertebras. These facets look nearly downward as in Nyctea, and the 

 small, sessile facets on the posterior walls of the neural canal, representing 

 the post-zygapophyses, look upward and somewhat outward. This is an 

 interesting exception to the well known rule of the position of zygapo- 

 physes, and the attention of the writer was first called to it by his assistant 

 in Palaeontology, Mr. Oscar Harger. 



The neural spine in this specimen is broken off, but is seen in section 

 to be hollow. The posterior articular face of the centrum is slightly more 

 concave than the anterior, and its upper outline is nearly straight. 



The second caudal of the series preserved considerably resembles the 

 preceding. As in that vertebra, the anterior articular surface is slightly 

 concave. In outline, this surface is a nearly regular oval. On the under 

 surface, the centrum is somewhat excavated, so as to appear hour-glass 

 shaped, expanding posteriorly to the articulation. The bases of the 

 transverse processes, as in the preceding vertebra, occupy the entire 

 lateral surface of the centrum. These processes are directed strongly back- 

 ward, outward, and somewhat more downward, than in the preceding 

 vertebra. The neural canal is much as in that vertebra, or perhaps slightly 

 smaller, and the pre-zygapophyses are well developed, and supported 

 articular facets. They are smaller than in the vertebra in front, and post- 

 zygapophyses are not to be distinctly seen, partly, however, it may be, 

 from the imperfect condition of the specimen. The neural spine is broken 

 away in this vertebra. The posterior face of the centrum is slightly con- 

 cave, like the anterior, and is a little more transverse, with the upper 

 outline nearly straight. 



The third caudal preserved in the present series is rather less perfect 

 than the two preceding it, but has the transverse processes in fair preserva- 

 tion. The centrum has been crushed from above downwards, but its 



