EDENTATA OF THE SANTA CRUZ BEDS. 299 



each side. The nasals are long and narrow and quite convex in both 

 directions ; they are narrowest at the frontal suture and, broadening regu- 

 larly forward, are widest at the anterior end ; there is no lateral notch or 

 process, but each nasal is obliquely truncated, so as to form a short, 

 blunt, median point. The premaxillaries are not known, but the facets 

 for them upon the maxillae indicate that they probably resemble those of 

 Hapalops in shape, except for their extreme shortening. The preorbital 

 portion of the maxillaries is rather long, owing to the posterior position of 

 the orbit; the preorbital fossa is usually small and shallow, though it is 

 sometimes well defined, and is always very narrow ; the dorsal portion of 

 the maxillary is incurved and forms much of the roof of the nasal cham- 

 ber; the zygomatic process of the maxillary is much less prominent than 

 in Hapalops and the infraorbital foramen is narrow, hardly more than a 

 slit. The bony palate and posterior nares show no important differences 

 from those of the latter genus. 



The cranial foramina differ from those of Hapalops in only a few par- 

 ticulars ; the optic foramen is placed lower down and nearer to the fora- 

 men lacerum anterius, which is farther removed from the united foramina 

 rotundum and ovale ; the glenoid foramen appears to be wanting, and 

 the venous foramina along the parieto-squamosal suture are few and 

 inconspicuous. 



The mandible has a very short, deep and thick horizontal ramus, with 

 strongly convex ventral border ; the predental beak is very short and at 

 the anterior end is broader than in any of the preceding species; the 

 symphysis is very short and the chin almost vertical. The ascending 

 rami are convex externally and concave internally, a peculiarity which is 

 not repeated in any other contemporary genus ; the anterior border of the 

 ascending ramus is quite broad at the base and is made concave by the 

 prominence of the linea obliqua interna; the coronoid, which varies much 

 in' height, is incurved, recurved and bluntly pointed, and the sigmoid 

 notch is narrow and shallow ; the condyle is set upon a long neck and is 

 curved mesially, presenting inward almost as much as upward ; of the 

 angle only enough is preserved to show that it was inflected. The 

 postero-external opening of the dental canal is at the base of the linea 

 obliqua externa; the mental foramen is single and presents forward. 



