468 THE WASATCH FAUNA. 



molar of Bhinocerus. No internal posterior tubercle, so that the fourth 

 premolar is unlike the first true molar. 



The first and second inferior true molars are subequal, while the third 

 is smaller. The former support three posterior tubercles and two anterior 

 opposite each other. The median posterior is smaller than the others, and 

 does not give the posterior edge of the crown an angulate outline. The 

 section of the interior tubercles is round; that of the exterior is crescentic, 

 the anterior horn extending into a low "ridge which, in the case of the pos- 

 terior tubercles, reaches the anterior inner tubercle. In the first true molar 

 it extends round the anterior base of the crown as a wide ledge ; in the 

 second and third molars this ledge is much less distinct. The median poste- 

 rior tubercle of the third true molar forms a prominent heel, but its prom- 

 inence is less obvious because of the proximity of the inner median tuber- 

 cle which is not opposite the external median, but posterior to it. No cin- 

 gula on the external or posterior side of the teeth ; inner side concealed by 



matrix. 



Measurements of shull. 



Length of cranium from apex of premaxillary bone to superior border of foramen magnum, 



inclusive; measured below 145 



Liength from apex of premaxillary to a vertical line from end of nasal bone 0185 



Length from end of premaxillary to anterior edge of orbit 064 



Length from end of premaxillary topostglenoid process 116 



Long diameter of meatus auditorius externus 006 



AVidth of i)alate between canines 015 



Width of palate between postglenoid processes, exclusive 027 



"Width of occiput at foramen magnum 038 



Width (least) at anterior iiarietal region 016 



"Width at postorbital processes 036 



"Width of interorbital space 035 



Greatest width of anterior nares 013 



Greatest depth at front of orbit (without molar) 036 



Greatest width at zygomata 055 



Length of mandibular ramus 110 



Depth of mandible at condyle 042 



Depth at heel of third true molar 020 



Depth at second true molar 017 



Depth at first premolar Oil 



Length on palate from premaxillary border to line of canine alveolus 019 



Length of canine alveolus - - 0065 



Length of molar series 053 



Length of premolar series 030 



Length of base of second premolar 0065 



_,. . . T, ™ ...< anteroposterior 007 



Diameters superior P-m. iii < . ^ „„^ 



* transverse 00b 



