BUNOTHBRIA. 803 



The intervertebral foramina are quite large, and the narrow neurapophyses 

 are almost entirely occupied by the bases of the diapophyses. These are 

 well developed, obliquely tnincate below at the end, and grooved on the 

 under side of the shaft. The neural spines are elevated, narrow, and acute 

 in front. The ribs are flat, and the capitular and articular faces are well 

 developed. 



The prcesternum is shaped somewhat like the sternum of a bird. It has 

 a prominent inferior longitudinal keel, which disappears posteriorly, leaving 

 a vertically-oval face of articulation for the second sternal segment. The 

 superior face is slightly concave, and the only lateral articular faces are 

 those for the attachment of (?) first ribs, and are of considerable size, and are 

 adjacent to the anterior extremity. The borders of the bone are but little 

 contracted behind them. The scapula is elongate, and has an elevated 

 crest, descending abruptly near the glenoid ca\'ity. The latter is an elon- 

 gate oval, the border at one end more produced than at the other, and ter- 

 minating in a short hooked coracoid. 



The humerus has a protuberant head and shaft, and condyles much 

 flattened. The head is nearly 180° in arc, is posteriorly directed, and of 

 compressed form. On the inner side is a depressed tuberosity for the pec- 

 toralis muscle, while opposite to it the greater tuberosity rises as high as 

 the head, parallel to it. Distally, the condyles are continuous, nearly con- 

 cave, and supplemented by huge inner and a smaller outer epicondyles. 

 There is no supracondyloid foramen, but a strong arterial foramen. 



The cast of almost the entire brain is preserved, and, as the parietal 

 bones are wanting, the proportions are clearly traceable. The olfactory 

 lobes are broken off. The superior face of the hemispheres and cerebellum 

 together have a subquadrate outline, a little wider than long. The cere- 

 bellum is completely exposed behind the hemispheres, and is strongly angu- 

 late at its upper posterior border to fit the inion. The vermis is nearly as 

 wide as each lateral lobe. The surface of the hemispheres is smooth, and 

 the sylvian fissure distinctly indicated. 



As compared with other forms, the following points may be observed: 

 In Chrysochloris and Centefes, as above noted, the external cusps of the 

 superior molars are wanting. In the genera in which they are present, as 



