Peterson: Uinta Titanothere Dolichorhinus. 



131 



rhinoceros. However, the bone as a whole, especially its anterior 

 border, is relatively heavier than in the tapir. The thyrohyal is 

 unfortunately broken off on both sides. This element was perhaps 

 relatively less developed than in Tapirus terrestris. The ceratohyal 

 is also unfortunately broken ofif at the upper end, but its length was 

 no doubt proportionately equal to that of the American tapir, 

 while the shaft is less constricted antero-posteriorly. The epihyal is not 

 present; this bone no doubt was nodular in character, as is the case in 

 Tapirus terrestris. The anterior portion of the shaft of the stylohyal 

 is rounder in cross-section than in the tapir or the horse, but the upper 



Fig. 3. Side view of hyoid apparatus. Figs, i and 3. 

 (?), No. 2865; Fig. 2. Tapirus terrestris, H nat. size, th 

 hyal, ch = ceratohyal, eh = epihyal, sh = stylahyal. 



Dolichorhinus longiceps 

 = thyrohyal, hh = basi- 



end is flattened and terminates in enlarged processes, the superior 

 attached to the hyoidial portion of the temporal bone and the inferior 

 somewhat more obtusely rounded, extending downwards and out- 

 wards. This rib-like upper end of the stylohyal is more suggestive 

 of the rhinoceros or the horse than of the tapir. • (See Figs. 3 and 4.) 



Measurements. 



Length of skull from anterior border of the orbit to top of occiput 365 mm 



Antero-posterior diameter of upper molar series 125 



Transverse diameter of frontals at postorbital processes i45 



Depth of mandible at M^^ 7i 



Length of stylohyal, approximately 16S 



Antero-posterior diameter of basihyal, median line IS 



