MERYCOIDES 



175 



Specific Characters: The skull is decidedly long and narrow, being almost exactly twice as 

 long as it is wide and longer than that of the other two species in this genus. Another character 

 which distinguishes this from the other species is the presence of an oblong triangular facial vacuity 

 surrounded by the maxillary, lacrimal, and frontal bones. The zygomatic arches are widest just in 







Fig. 1 26. — Merycoides longicep (Douglass). Skull and jaw. HT. Cat. No. 9732 A.M.N.H. 2/5 nat. size. 



(After Douglass, 1907.) 



advance of the glenoid. The zygomatic part of the squamosal is slender and is very similar in 

 form to that of M. cursor, that is, the posterior part is neither high nor vertical. The anterior part, 

 however, extends farther forward beneath the orbit than in the other species. The malar is fairly 

 deep, as in M. latidens. The nasals are of the same general proportions but are truncated both 



Fig. 127. — Merycoides longicep (Douglass). Superior view of skull. HT. Cat. No. 9732 A.M.N.H. 2/5 nat. size. 



(After Douglass, 1907.) 



anteriorly and posteriorly, thus differing from M. cursor. They are convex in both directions and 

 widest at the narial opening. The lacrimal bone is large and spreads out on the face to include the 

 deep lacrimal fossa. The frontals are narrow, are mainly convex, with a depression just posterior to 

 the nasals, and extend anterior to the lacrimals. The orbits are small, nearly circular, and about 

 medially placed in the vertical plane. The temporal ridges unite considerably behind the fronto- 



