1910] 



Merriam: Fauna of Cedar Mountain Region 



185 



with the unciform. In metatarsal three there seems to be a very small 

 and quite oblique facet for the cuboid. In general the limb structure 

 resembles that of Hypohippus. 



Comparative Measurements op Dentition 



Milk dentition 



H. nevad- 



ensis 

 No. 21056 



H. affinis 



Type 

 specimen 



28.5 ap. 



26.7 a 

 29 



Permanent dentition 



Dm 2 , anteroposterior diameter along 



outer border 33 mi 



Dm 2 , greatest transverse diameter 29 



Dm 3 , anteroposterior diameter along 



outer border 31.8 



Dm 3 , anteroposterior diameter meas- 

 ured through protoconule and 

 hypostyle 29 



Dm 3 , greatest transverse diameter 30.5 



Dm 4 , anteroposterior diameter along 



outer border 31.9 ap. 



Dm 4 , anteroposterior diameter meas- 

 ured through protoconule and 

 hypostyle 



Dm 4 , greatest transverse diameter 31.4 



a, measurements from J. Leidy 's figure of type specimen. 



b, from W. B. Scott's figures of type specimen. 

 ap, approximate. 



H. 

 osborni 



P 2 

 P 2 



27.3 

 26 



25.4 



24 

 30 



25 

 30 



H. 

 equinus 



25 

 25 



22 b 

 27 



25 



22 b 

 26 



Measurements of Limb Elements, No. 21056 



Eadius, greatest length of shaft 241 r 



Radius, least width of shaft 25 



Metacarpal II, greatest length 190 



Metacarpal III, greatest length 192 



Metacarpal III, width of distal end, approximate 28.5 



Phalanx I, digit III of anterior extremity, greatest length 40 



Phalanx I, digit III of anterior extremity, greatest width 30 



Phalanx II, digit III of anterior extremity, greatest length 30 



Phalanx II, digit III of anterior extremity, greatest width 31 



Metatarsal III, greatest length 203 



Metatarsal IV, greatest width at proximal end 17 



Phalanx I, lateral digit (hind foot?) greatest length along 



superior side 23.5 



Phalanx III, lateral digit (hind foot?) length along superior 



side 35 



Relationships. — The form represented in specimen no. 21056, resem- 

 bles Hypohippus in the characters of the limbs and in general form 

 of the cheek-teeth. It differs from Hypohippus in the separation of 

 metaloph and ectoloph in the milk dentition. It is uncertain whether 

 the permanent dentition of this species is represented in any of the 



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