FORT UNION OF CEAZY MOUNTAIN FIELD, MONT. 53^ 



Aphronorus: Allied to Pentacodon of the Torre j on but apparently more primitive. 

 Eudaemonema: Allied to Mixodectes in the Torrejon and (perhaps more distantly) 



to other genera in Upper Paleocene and Lower Eocene, more primitive than 



any of these allies in some respects, but not on the same line of descent as- 



any of them. 

 Elpidophorus: An Upper Paleocene genus but here with a distinctive primitive 



species, which may weU prove generically separable. 

 Picrodus: Probably allied to Zanyderis of the Upper Paleocene, relative degree 



of specialization not determinable. 

 Pronothodedes: Allied to Plesiadapis of the Upper Paleocene but distinctly more 



primitive. 

 Elphidotarsius: Allied to Carpodaptes and Carpolestes of the Upper Paleocene but 



distinctly more primitive than either. 



7-, 7 7., [Generally primitive genera, but exact lines of descent not clear 



Palaechthon } \ ^ / . . ... 



„ , ,,, enough for more precise use m correlation. 



Palenochtha] 



Conorydes: Genus otherwise Middle Paleocene as far as definitely known, species 



imperfectly represented but indistinguishable from C. comma of the Torrejon. 

 Psittacoiherium: Genus otherwise certainly known only in Middle Paleocene^ 



species indistinguishable from P. multifragum of the Torrejon. 

 Claenodon: Genus otherwise chiefly Middle Paleocene but extending into Upper 



Paleocene in this field, species more primitive than that commonest in. 



Torrejon, more comparable to but perhaps slightly more primitive than the 



second Torrejon species. 

 D enter ogonodon: A distinctive genus not known elsewhere, perhaps especially 



allied to, but if so distinctly more advanced than, Proto§onodon of the Puerco. 

 Proihryplacodon: Allied to Thryptacodon, Upper Paleocene and Lower Eocene,, 



but more primitive. 

 Metachriacus] j Genera, unknown elsewhere, of Paleocene aspect but not more 

 Spanoxyodonjl closely useful in correlation. 

 Mimotricentes: Perhaps especially allied to Tricentes, Middle Paleocene, and if so 



slightly more primitive, but probably on a diflFerent line of descent. 

 Didymidis: Genus Middle Paleocene to Lower Eocene, relationship of two species 



not clear enough for more exact correlation, but a third indistinguishable 



from D. haydenianus of the Torrejon. 

 Ididopappus: Unknown elsewhere, perhaps especially allied to Viverravus of the 



Eocene, but if so more primitive. 

 Dissacus: Genus Middle Paleocene to Lower Eocene, species not identifiable. 

 Ellipsodon: Genus otherwise only positively identified in Middle Eocene, species 



close to E. acolytus, Torrejon, perhaps slightly more advanced or on different 



line of descent. 

 Litaletes | [ Genera unknown elsewhere, general aspect Paleocene, perhaps 

 Litomylus \ \ rather more Middle Paleocene, but not exactly determinable as 

 Haplaletes] [ to evolutionary position. 

 Telradaeiiodoit: Genus typically Middle Paleocene, probably reaching Upper 



Paleocene in this field, two species close to those from Torrejon, one of them 



indistinguishable. 

 Coriphagus: Genus otherwise only in Torrejon, species closely allied. 

 Anisonchus: Genus Lower and Middle Paleocene, also Upper Paleocene in this 



field only, species same as in Torrejon, but probably also reaches Upper 



Paleocene here. 

 Pantolamhda: Genus certainly identified only in Middle Paleocene, species allied 



to those of Torrejon. 



