1884.J 507 [Cope. 



for the succeeding pairs of nerves perforating the neural arches. The atlas 

 is not very elongate. The base of the diapophysis has a perforating canal, 

 which issues in a large inferior fossa. The vertebrarterial canal then per- 

 forates the diapophysis upwards anterior to the middle of the base, and 

 then soon enters the neural canal just posterior to the superior margin of 

 the cotylus of the occipital condyle. 



The centra succeeding the cervicals increase gradually in length poste- 

 riorly. Those of the anterior part of the dorsal series are quite depressed, 

 but the vertical diameter rapidly increases, so as to be equal to the trans- 

 verse in some of the lumbars. A trace of the opisthocoelous articulation 

 exists throughout the dorsals but is very little marked in the posterior 

 centra. There are no hypapophyses on the dorsals, but on one of them, 

 probably the third, the inferior and lateral faces are separated by a strong 

 angle, which is strongest anteriorly, giving the articular face a subquadrate 

 outline. The rib-bearing diapophyses are robust. On the posterior dor- 

 sals the capitular and tubercular surfaces are confluent, forming a narrow 

 facet on the anterior face of the diapophysis, in a manner not seen in 

 Cervus elaphus or Sus scropha. The centra of the lumbars, after lengthen- 

 ing, become shorter immediately in front of the sacrum. The vertical 

 diameter of one or two posterior ones is less than that of the anterior 

 ones. The greater number of the lumbars display a small compressed 

 hypapophysis at their anterior extremity ; but this is wanting on the 

 posterior ones. The neural arches of the dorsal and lumbar vertebrae are 

 nowhere perforated for the spinal nerves. 



The lumbar prezygapophyses embrace the articular faces of the poste- 

 rior ones, which have a section of one side (below), the end (external), 

 and a half the other side (above), of a transverse ellipse. The superior 

 recurved surface does not appear. 



The sacrum consists of five vertebrae, with very depressed centra. The 

 ilium is attached to the diapophysis of the first, and a small anterior por- 

 tion of that of the second. That of the fourth is flat and free. The an- 

 terior zygapophysis of the first displays a slight degree of the superior 

 incurvature general in Artiodactyla. The caudal vertebrae were numerous, 

 forming a long tail. The proximal ones are moderately depressed, while 

 more distal ones with wide diapophysis and complete neural arch, are sub- 

 cylindric, and more elongate. The number of vertebrae preserved in the 

 most complete of my specimens, is as follows : 



Cv. D. L. S. Cd. 



0. culbertsoni ad 7 5 6 4 4 



0. culbertsoni juv 5 8 6 2 1 



0. gracilis 4 5 3 * * 



0. g. color adoensis 7 8 6 5 3 



An anterior, perhaps second, sternal segment is flat and subquadrate in 

 outline, with large haemal articular face of the lateral margin anteriorly, 

 and a small one posteriorly. No inferior carina. 



