84 Annals of the Carnegie Museum. 



long pes, but whether this is a specific character, or whether it holds 

 good throughout the genus Protoreodon, cannot be determined until 

 more complete material of other species is secured. 



In this connection it is well to draw the attention of students to 

 the fact that Professor Scott's figure 22 of Plate 3 of his Uinta report 

 {Trans. Wag. Free Inst, of Science, Vol. VI, 1899) very probably repre- 

 sents a hind foot of this species. The hind foot and other fragments 

 of limbs illustrated in the " Mammalia of the Uinta Basin," Plate VII, ^^ 

 also possibly pertain to Protoreodon medius. 



M EASUREMENTS. 



Type No. 2962. 



Length of skull (occiput to and including premaxillaries) 173 mm. 



" (occiput to end of nasals) 168 



" " cheek-dentition (upper) 73 



" canine to M- 29 



" " molar series 37 



Greatest length of mandible 127 



Length of cheek dentition (lower) 74 



Depth of ramus at M^ 31 



Length of humerus head to distal end 137 



Greatest transverse diameter humerus, distal end 27 



Length of Mc. IV, approximately 43 



Greatest antero- posterior diameter of humerus, distal end 19 



" length of femur 153 



" tibia : . . . 143 



" " " astragalus 26 



" " " calcaneum 50 



Height of tarsus including astragalus 37 



Length of Mt. IV, dorsal measurement 65 



Restoration of Protoreodon medius (Plate XLI). 



From the study of the articulated skeleton of Protoreodon medius 

 it becomes plain that the genus combines some of the characters of 

 Merycoidodon and of Agriochccrus of the White River Oligocene. Thus 

 the neck, the trunk, and the caudal region almost duplicate those of 

 Agriocha'rus, while the structure of the limbs, and especially of the 

 foot, more nearly suggests Merycoidodon. Professor \V. B. Scott long 

 ago pointed out very clearly the relationship between Protoreodon, 

 AgriochKrus, and Merycoidodon.'^^ Indeed as early as 1875 Professor 



^2 Trans. Amer. Philos. Soc, 'Vol. XVI, 1889, PL \'II. 



''5 "The Mammalia of the Uinta Formation," Amer. Philos. Soc, Vol. XVI, 

 Part II, 1889, pp. 487-503. 



