454 SMITHSONIAN MISCELLANEOUS COLLECTIONS [vol. 50 



The alveoli are directed downward, forward, and outward. They 

 are all somewhat flattened and elliptical in outline, but some of the 

 posterior ones are more nearly circular. The bony septa between 

 them are all incomplete in the specimen, but were probably complete 

 originally and at least half as broad as the alveoli. On the right 

 side, 65 alveoli can be counted, and as the rostrum is nearly complete, 

 this was probably about the original number of teeth. 



The nares are small and have a longitudinal diameter of 15 mm. 

 The posterior vertical free border of the vomer is concave and ends 

 abruptly on meeting the surface of the basisphenoid. The free mar- 

 gins of the inferior lateral borders of the basisphenoid are very rough. 

 The basioccipital is lacking, except a small fragment attached to 

 the occipital condyle. Only the left condyle is present. It is 45 mm. 

 high and 30 mm. broad. It is closely appressed to the surface of the 

 exoccipital, the outer margin being only 9 mm. at most from that 

 surface. . 



Only the left zygomatic process of the temporal is present. It is 

 75 mm. long from its articulation with the exoccipital to the anterior 

 free end and 51 mm. from the tip of the postglenoid process to the 

 lower margin of the temporal fossa. Enough of the posterior mar- 

 gin of the temporal fossa remains to indicate that it was nearly 

 semicircular, and that it extended backward little, if any, beyond the 

 line of the occipital condyles. The glenoid surface of the zygomatic 

 is 41 mm. broad and only slightly concave. The free margin is quite 

 thin, both laterally and in front. The exoccipital terminates in a 

 semicircular process, with the end truncated and deeply pitted. 



The length of the symphysis of the mandible is 444 mm., and when 

 complete was probably but little longer. At the middle of its length 

 the breadth is 28 mm. On the line of the posterior end of the sym- 

 physis the breadth is 50 mm. and the depth 29 mm. The superior 

 surface of the symphysis is flat, with a median groove, which is 

 about 2 mm. broad at the middle point. It dies away gradually 

 anteriorly and is bifurcated posteriorly. The tooth-row extends about 

 23 mm. beyond the posterior end of the symphysis. The internal 

 surface of the anterior end of the rami is convex, the external sur- 

 face nearly plane, and the inferior margin rounded. The rami 

 diverge at an angle of about 45 °. The apex of the angle is rounded. 



The inferior surface of the symphysis is rounded and is divided on 

 each side by a very distinct groove, which is deepest posteriorly, 

 becomes shallower anteriorly, and disappears near the tip of the 

 jaw, where the surface is nearly flat. The bottom of the groove is 

 occupied by several foramina, which are prolonged into narrow 



