1915.]| Matthew and Granger, Lower Eocene Wasatch and Wind River Faunas. 433 
derived from our Paleocene faune, as in both Puerco and Torrejon horizons 
we find a large and diversified element of Creodonta, which is absent from 
the South American faunze where carnivorous marsupials take its place. 
The reference of a mammal from our lower Eocene to this distinctively 
South American group will naturally appear questionable to many paleon- 
_ tologists, especially since the evidence rests at present only upon a lower 
jaw. Were the pattern a primitive and generalized one or were the re- 
semblance in superficial or adaptive characters of the teeth I should 
regard it as inadequate. But the agreement lies not in superficial resem- 
blances but in the peculiar fundamental pattern of the molar teeth which 
is the principal reason for regarding these South American ungulates as 
related to each other and distinct from the northern groups. If Arcto- 
stylops is not a member of this southern group, we must conclude that this 
peculiar pattern has also arisen independently in some northern group of 
mammals. This would be a somewhat remarkable coincidence indeed, 
but not inconceivable, and tenable were there sufficient evidence that the 
genus was not related to the Notoungulates. But I can find nothing in the 
teeth or jaw characters that would afford a reason against reference to the 
Entelonychia. It may indeed be difficult to reconcile with certain hypoth- 
eses of the time and place of origin and evolution of these South American 
placentals. That is an excellent reason to verify and sift the evidence 
critically; it is hardly a reason for rejecting it. 
OrDER PRIMATES. 
The two families here referred to the order, the Adapide (including 
Notharctide as a subfamily) and Tarsiide (Anaptomorphide) are Primates 
beyond reasonable question. Some or all of the genera of the families 
Apatemyide and Mixodectide, here placed as Insectivora, may when 
better known have to be transferred to the Primates. This is true especially 
of Trogolemur in the former and of Cynodontomys and Microsyops in the 
latter family, in which the dentition, save for the double-rooted upper 
canine of Microsyops, is of a type very like the known Eocene primates. 
Vismie ADAPID ©. 
1Pachylemuride MtIAuu 1875, Filhol 1876. 
Adapide TrovEssart 1879, Revue et Magaz. de Zool. 3° ser. t. vil, p. 223; CoPE 
1885, Amer. Nat., Vol. XIX, p. 459; Wortman 1903, Amer. Journ. Sci., Vol. AY, 
p. 174; ScutossER 1911, in Zittel’s Grundz. d. Pal., Vertebrata, p. 546. 
1 Not available because not based on a genus. 
