238 



TEN YEARS PROGRESS IX VERTEBRATE PALEONTOLOGY 



' Pelycodus 



Anaptomorphus 



. Cyn odon tomys 



uidymictis 



i^ivercavus 



Miacis ana l/u/pa^us 



fassacyon 



C/aenoaon 



Anacodon . 



Pa/asonict/s 



Oxyasna 



I. imnocyonid 



S/nopa 



Hapalodectes 



Oissacus 



Pachyasna 

 , ■ Pa/seosinopa 

 . MyopsodOs 

 { ? Metache/romys 



< Paramys 



< Calamodon 

 { Trigonolestes 



!?Heptodon 

 Eohippus 

 Systemodon 

 Phenacodus 

 Coryphodory ^ 



? Primate 

 { Didymictis 



< Limnocyon 

 \ ?Pa/asonictis 



Metacheiromyid 

 [ EsthonyJr 

 \ ?£sthonyc^id 

 I Phenacodus 

 \ ?Phenacodont 

 [Bathyoftsis 

 \ Coryphodon 



■^Composite section below unconformity 

 Oc^\irsncc. o^ Sathyopsis r*sp. and 

 ZuTinocytJ^ puzzling 



Figure 4. — Oeneralized Section — Loiver Eocene of Big Horn Basin, xcesiern Wyoming 



(After Granger and Sinclair) 

 Upper: Larnhdotlierium Zone, "Wind River" 

 Middle : Transition Zone, "Lj'site" 

 Lower : Coryphodon Zone, "Kniglit" 

 Ijower : Lower Coryphodon Zone, "Ralston" 



