438 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 53. 



Some minor features of the skull need to be mentioned. The inter- 

 orbital region is flat, even a little concave. From the middle of the 

 brain case the outline descends rather strongly to the occipital crest. 

 The infraorbital foramen is situated unusually high. The space be- 

 tween the orbit and the foramen just named is swollen, being con- 

 vex, not concave as it is in the domestic horse. The maxillary ridge 

 is less prominent than in the domestic horse. The condylar foramen 

 is in wide communication with the foramen lacerum posterius. The 

 palate is more strongly vaulted than that of the domestic horse. 



The teeth are in fine condition. They are, however, considerably 

 worn, and to this perhaps is due to some extent, but not entirely, 

 their unusual breadth and the great simplicity of the enamel. The 

 premolars and molars appear to be worn down to about one-half of 

 their original length. The last premolar has a height of 40 mm. 

 The lower incisors are worn so that the cups have disappeared, but 

 these are still present in all of the upper incisors. The following are 

 the measurements: 



Measurements of the upper teeth. 



mm. 



Length of premolar-molar series 167 



Length of premolar series 87 



Length of molar series 77 



Pm', length 36 



width 28 



protocone 12 



Pra', length 25. 5 



width 28 



protocone 17 



Pm*, length 26 



width 29 



protocone 1 17 



M\ length 22. 5 



width 27 



protocone , 14 



M», length 24. 4 



width 27 



protocone 16 



M', length 27 



width 24. 5 



protocone 19 



^fcasnremcnts of the lower teeth. 



Length of premolar series 83 



Length of molar series 80 



Pms, length 31 



width 17. 5 



Pma, length 26. 5 



width 19 



Pm*, length 26. 5 



width 18. 8 



Ml, length 22. 5 



width 16. 5 



Mj, length 26 



width 16. 5 



Mj, length 32 



width 16 



