312 University of California Publications in Geology [Vol.7 



to the lamboidal crest. The region of the occiput immediately 

 above the foramen magnum is moderately convex, approaching 

 flatness, as in Camelus, instead of strongly convex nearing 

 angularity, as in Auclienia. 



The frontal foramina are a little farther apart than in 

 Camelus. In Attehcuia these foramina are relatively larger and 

 there are distinct channels leading forward from them such as 

 are not seen in the Rancho La Brea specimens. The infraorbital 

 foramen and the foramen piercing the root of the zygomatic arch 

 are situated much as in Auclienia. The infraorbital foramina 

 consists of a single opening on each side in no. 20028; the open- 

 ing is separated into two parts by a bridge of bone in 20040 ; 

 and is divided on one side by a slender bridge in 20049. The 

 infraorbital foramina are situated approximately over the pos- 

 terior border of P 4 in nos. 20028 and 20040, and over the middle 

 region of M 1 in no. 20049. The anterior palatine foramina are 

 long and narrow, and extend back to the canines. The anterior 

 ends of the maxillaries extending around the borders of these 

 foramina reach to the anterior side of the openings, as in the 

 type of Camelops. In Auclienia lama they do not reach as far 

 forward. The posterior palatine foramina are situated well for- 

 ward near P 3 in specimen 20028, and opposite P 4 in nos. 20040 

 and 20049. 



The postglenoid foramen is very small, in contrast to the large 

 size of the opening in Camelus. A small foramen present on the 

 outer base of the postglenoid process is not found in Camelus 

 and is absent or very minute in Auclienia. The lateral foramina 

 of the occiput are very large and open externally into the deep 

 lateral fossae of the occipital region. The anterior mental 

 foramen of the mandible is immediately below or slightly behind 

 the canine, as in Auclienia. It is situated farther back on the 

 horizontal ramus in Camelus. 



In the mandible (figs. 3, 6, and 8), the symphsial region is 

 relatively short anteroposteriorly, as in Auclienia. The sym- 

 physial union in Camelus is much longer anteroposteriorly 

 than in Auclienia or in the Rancho La Brea specimens. The 

 horizontal ramus is somewhat higher than in Camelus, and 

 slightly higher than in Auclienia. It tapers very gradually 



