212 The American Geologist. October, 1905 
Edentates in North America has come to hand in the dis- 
covery of Dasypoda in the Middle Eocene (Osborn 1 ). 
Another observation which may prove to have very 
broad phylogenetic bearings is the evidence of arboreal an- 
cestry in the structure of the feet of the Creodonta, Condy- 
larthra and Amblypoda (Matthew) ; it has not yet been as- 
certained whether this evidence is of the same nature as that 
which exists in the feet of the Marsipials (Huxley, Dollo, 
Bensley). With this exception attempts to bring these 
essentially archaic Placentals nearer to the Marsupials have 
not been successful." The single direct link with the higher 
Placentals which has even been alleged to occur in these 
beds is the supposed Viverravus of the Torrejon. The 
opinion has therefore been expressed (Osborn 3 ) that these 
animals should be sharply separated from the higher pla- 
centals and placed in the Meseutheria. 
Among the unsolved problems in this Basal Eocene 
fauna is also its source, or ancestry, which has only in part 
been traced into the Cretaceous fauna. We require fuller 
evidence as to the relationship with the Notostylops fauna 
of Patagonia (Ameghino), also a positive demonstration 
that the Tseniodonta are really ancestral to the Edentata. 
In other words, the phylogenetic connections of these. Basal 
Eocene Placentals of North America and Europe are cir- 
cumscribed; the sanguine view of Cope that they contain 
the sources of the modern Placentals which first appear in 
the Lower Eocene has not been realized; none of these ani- 
mals give us the stem forms of the true Carnivores, Peris- 
sodactyls or Artiodactyls of the Lower and Middle Eocene. 
Lower, Middle and Upper Eocene Faunas 
The chief geological and faunal progress has been in 
the Bridger (Bartonien) and L T inta (Ligurien) stages, cor- 
responding to the Middle and Upper Eocene, which have 
at last been clearly and sharply divided into two successive 
faunal stages for the Bridger (Matthew, Granger), and two 
successive faunal stages for the Uinta (Peterson, Osborn). 
The importance of these divisions in the evolution of the 
1 An Armadillo from the Middle Eocene {Bridget) of North American 
Bull. Amer. Mus Nat. Hist., vol. xx, 1904, pp. 163-165. 
2 Wortman. Studies of Eocene Mammalia in the Marsh Collection. 
Part. I, Carnivora. Amer. Jour. Sci.. vols, xi-xiv, 1901, 1902. 
3 A Division of the Euthcrian Mammals- Trans. N. Y. Acad. Sci., 
June 1, 1S94, p. 234, 
