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UINTA SELENODONTS 



tylopodan features in the structure of the oreodonts, and spoke of the family as 

 uniting characteristics of the deer, camel, and hog. ('69, p. 71.) This phrase, 

 however, should probably be regarded as descriptive rather than as expressing 

 an opinion upon the taxonomic question, concerning which Leidy seems to 

 have held no decided views. Cope brought the family into relation with the 

 tragulines ('88, p. 1084), but here again, as in so many of Cope's phylogenetic 

 schemes, the connection seems to have been regarded as formal and technical 

 rather than actual. Marsh ('77, p. 365) has vaguely expressed an opinion 

 according to which the nearer allies of the oreodonts are to be sought for 

 among the anthracotheres (Hyopotamus or Ancodus) of the Old World. Sub- 

 stantially the same opinion is elaborated in my monograph of the family. 

 ('o,itf, p. 391.) Rutimeyer ('S3, p. 98) in a very brief and cursory way ex- 

 pressed his belief that the oreodonts are nearly related to the camels, and 

 speaks of the " in Nordamerika so stark vertretenen Vorlaufern der Camelina 

 (Oreodon, Procamelus, Leptauchenia, etc.)." Schlosser has adopted the same 

 view ; he says of the family : " Sie nehmen uberhaupt eine ganz eigenthumliche 

 Mittelstellung zwischen den Suiden und den Traguliden ein" ('87, p. 46), 

 " Von den altesten Oreodontiden haben sich wohl die Tylopoden abgezweigt" 

 (p. 48). From the same ancestral stock Schlosser derives the anoplotheres, 

 anthracotheres, hippopotamuses, and suillines. ('87, Table, p. 42.) 



The testimony of the Uinta selenodonts, while not entirely conclusive, is 

 distinctly in favor of the opinion held by Rutimeyer and Schlosser, — namely, 

 that the oreodonts are related to the Tylopoda, or rather that that term should 

 be employed in a broad sense, of subordinal value, and so extended as to in- 

 clude the oreodonts, and that the latter are an offshoot of the same stock 

 which gave rise to the modern camels and llamas. The recovery of the 

 Uinta fauna has for the first time made clear what a dominant position the 

 Tylopoda long held among North American artiodactyls, and how widely 

 ramified and diversified they became. We cannot yet, it is true, definitely 

 trace back the oreodonts to ancestors common to them and to the main line 

 of tylopodan descent, and until that is done the association of both groups in 

 one suborder must remain open to some question. On the other hand, it is 

 a highly important and significant fact that in the Uinta the gaps between the 

 various families of characteristically American selenodonts were not nearly so 

 wide as they afterwards became through the divergent courses of develop- 

 ment followed by these families, and that they were then obviously converg- 

 ing back to a common term. Even in Uinta times, however, the oreodonts 



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