FORMATIONS OF THE NACIMIENTO GROUP 729 



LIST OF FOSSILS FOUND IN THE PUERCO AND TORREJON 



FORMATIONS 



Mammalia* 

 Puerco Torrejon 



Polymastodon zone Pantolambda zone 



I. San Juan Basin, New Mexico i. San Juan Basin, New Mexico 



2. Fort Union formation (in part), 

 Montana 



MULTITXreERCULATA 



Neoplagiaulax americanus Cope ... X Neoplagiaulax molestus Cope. . . X 



Catopsalis foliatiis Cope X Ptilodus mediaevus Cope X 



Polymasiodon taoensis Cope X Ptilodus trovessartianus Cope. . . X 



Polymastodon attenuatus Cope X Ptilodus plicatus Cope X 



Polymastodon selenodus O. SindE. . X Ptilodus montanus Douglass X 



Ptilodus gracilis Gidley X 



Polymastodon fissidens Cope. ... ? 



CREODONTA 



Miacidae 



Didymictis haydenianus Cope.. . X 



Arctocyonidae 



Claenodon corrugatus (Cope) ... X 



( ?) Claenodon ferox (Cope) X 



? Claenodon protogonioides 



(Cope) X 



Mesonychidae 



Dissacus navajovius Cope X 



Dissacus saurognathus Wortman X 

 Triisodontidae 



Triisodon quivirensis Cope X Sarcothraustes antiquus Cope — X 



Triisodon heilprinianus Cope X Goniacodon levisanus Cope X 



Triisodon guadrianus Cope X Microclaenodon assurgens Cope.. X 



Oxyclaenidae 



Oxyclaenus cuspidatus Cope X Chriacus pelvidens (Cope) X 



Oxyclaenus simplex (Cope) X Chriacus baldwini Cope X 



Loxolophus hyattianus (Cope) X Chriacus truncatus Cope X 



Loxolophus prisons (Cope) X Chriacus schlosserianus Cope. . . X 



Loxolophus attenuatus O. and E.. . X Tricentes subtrigonus (Cope)... . X 



Carcinodon filholianus (Cope) X Tricentes crassicollidens Cope. . . X 



Paradoxodon rutimeyeranus (Cope) X Deltatherium fundaminis Cope. X 



* The arrangement of the Hst of mammals is that of Dr. W. D. Matthew. See 

 bibliography, No. 65. 



