DAKOTA AND NEBRASKA. 



101 



In Oreodon major the basi-occipital is much more strongly keeled relatively than 

 in the other species, and it appears narrower from the encroachment upon it laterally 

 of the auditory bullae. The basi-sphenoid is more convex transversely. 



The teeth of Oreodon major are identical in form with those of the other species. 



The measurements of the specimen of the skull of Oreodon major are as follows: 



Length from summit of inion to end of nose, 



Length from occipital condyles to incisive alveoli, . 



Height of inion from summit to lower edge of occipital foramen, 



Breadth just above the auditory meatus, 



Length of cranium from summit of inion to post orbital mai'gin, 



Extreme length from lateral border of inion to post-orbital margin. 



Breadth of cranium at anterior squamosal borders, 



Breadth of narrowest portion of cranium, 



Breadth at zygomata. 



Breadth at post-orbital arches. 



Breadth at anterior orbital margins, 



Breadth at ends of frontal angular processes, 



Breadth at canine alveoli, . 



Breadth at first molar alveoli. 



Breadth at last molar alveoli. 



Breadth at infra-orbital foramina, . 



Distance of supra-orbital foramina, . 



Length of face from post-orbital margin to incisive alveoli. 



Height of orbital entrance, . 



Transverse diameter of do., 



Length of alveolar border, . 



Length of hard palate. 



Breadth of hard palate between first true molars, 



Height of occipital foramen. 



Transverse diameter of do.. 



Length of parietal crest, 



Length of frontals, .... 



Length of the molar series, . 



Length of the true molar series, . . 



Length of the premolar series, 



Antero-posterior diameter of last molar. 



Transverse " " " 



Lines. 



112 



108 

 36 

 36 

 62 

 62 

 28 

 19 

 65 

 48 

 36 

 14 

 24 

 22 

 40 

 21 



7 

 60 

 14 i 

 11 

 63 

 60 

 IS 



9 



9 

 30 

 28 

 48 

 26 

 23 

 lOi 

 11 



