678 PBOCEEDINOS OF THE NATIONAL MUSEUM. vol. 57. 



pules, especially in the anterior half of each of these teeth. In this 

 last feature they show a decided advance in complexity of the milk- 

 teeth over those of either of the living genera of peccaries. This is 

 less pronounced in M. yennsylv aniens but this species also has more 

 complex milk-molars than either Tayassu or Pecari. 



Measurements of type in millimeters. 



Lower teeth and jaws. 



Anteroposterior Transverse 

 diameter. diameter. 



Canine 12. 7 9.0 



Pi 10. 6. 4 



Pa 11. 10.2 



P4 12. 5 13. 



Ml 13. 7 13.4 



Mi 15. 14. 



Ma 19. 7 13. 3 



Length of diastema behind canines 71. 



Length of diastema in front of canines 11. 2 



Vertical depth of symphysis, median line 19. 5 



Width of symphysis at narrowest point 24. 



Depth of jaw below first molar 70. 



Thickness of jaw below first molar 20. 



Width across both jaws below first molar 70. 



Width of jaws at canines 35. 



Width between canine alveoli 15. 



Upper cheek teeth. 



Anteroposterior Transverse 

 diameter. diameter. 



P' 10. 3 11. 8 



P' 12. 3 13. 8 



M' 14. 14. 5 



M' 15. 15. 



M" 16. 13. 



Measttrements of upper milk teeth {specimen No. 8106). 



Dp' 10. 7. 5 



Dp' 12. 5 9. 



Dp^ 12. 11. 5 



M' 14. 11. 5 



EXPLANATION OF PLATES. 



Plate 54. 



(About one-fourth natural size.) 



Upper — Platygonus cf. cumierlandensis. Top view of skull No. 7992, U.S.N. M. 



LowEB — Platygonus cumierlandensis. Top view of skull No. 8000, U.S.N.M. 



(Showing supposed extremes of variation.) 



Plate 55. 



(About one-fourth natural size.) 



Uppek — Platygonus cf. cumierland-ensis. Palate view of skull No. 7992, U.S.N.M. 



Lower — Platygonus cumierlandensis. Palate view of skull No. 8000, U.S.N.M. 



(Shomng supposed extremes of variation.) 



