924 THE JOHN DAY FAUNA. 



side of the centrum is sharply defined laterally by an acute border extend- 

 ing posteriorly from the base of the diapoi^hysis. The anterior articular 

 face of the centrum is a transverse oval, looking a little downwards. 



The capitular rib-facets of the dorsal vertebrae are quite small, making 

 very slight emarginations of the borders,, and those of the last thi'ee verte- 

 brae are entirely on the anterior portion of each centrum The first dorsal 

 is not keeled below, and the second has a slight downward projection of 

 the anterior border. All the other centra are rounded below, and their 

 articular extremities are halves of circular disks, except those of the last, 

 which are more depressed. The centra increase matei'ially in lengtli pos- 

 teriorly, and the elontjate ones show traces of the keel, which is well 

 marked on the lumbars. On the antepenultimate centrum an angle of 

 the circumference of the posterior ai-ticular face appears just below the line 

 of the neural canal. On successive centra it becomes more prominent, and 

 descends to the inferior plane. It is so prominent as to be a process on 

 each side on the first lumbar. The succeeding lumbai-s increase in length 

 so as to be twice as long as the anterior dorsals; indeed, nearly three times 

 as long as the first dorsal. They have a low inferior keel, a lateral angle 

 extending from the diapophysis, and a low keel -like neural spine ex- 

 tending the length of the neural arch. The diapophyses have short and 

 narrow bases at the anterior extremity of the centrum. They commence, 

 as usual, as lateral ridges on the dorsals. The first ridge is visible on the 

 penultimate dorsal, extending obliquely backwards and upwards from the 

 superior border of the capitular facet. The anapophyses are very large on 

 the last three dorsals and the first lumbar. They are small on the antepe- 

 nultimate lumbar, and absent from the last two. The metapophyses are 

 first developed on the penultimate dorsal. On the first lumbar they are 

 large, and have enlarged rounded summits. They are absent from the last 

 three lumbars. The last lumbar is short, as in most carnivora, and has a 

 rather low neural spine, which extends along tlie entire length of the neural 

 arch. There are three sacral vertebrae, which have a keel for neural spine, 

 which is most elevated on the last. Four caudal vertebrae are in place, 

 succeeding the sacrum. They all have well-developed diapophyses, which 

 are directed backwards and are of depressed section. The neural arch is com- 



