ILLUSTRATIONS 



Plates 



(All plates following page 58.) 



1. Mullituberculates and insectivores from the Bison basin Paleocene. 



2. Primates and marsupials from the Bison basin Paleocene. 



3. Pronothodcctes from the Bison basin Paleocene. 



4. Plcsiadapis from the Bison basin Paleocene. 



5. Triccntcs and Chriacus from the Bison basin Paleocene. 



6. Thryptacodon from the Bison basin Paleocene. 



7. Clacnodon from the Bison basin Paleocene. 



8. Litomylus and Protoselcnc? from the Bison basin Paleocene. 



9. Haplaletes and Gidleyina from the Bison basin Paleocene. 



10. Phcnacodusl from the Bison basin Paleocene. 



11. Condylarths and Titanoidcs from the Bison basin Paleocene. 



12. Caenolambda from the Bison basin Paleocene. 



13. Caenolambda from the Bison basin Paleocene. 



14. Caenolambda from the Bison basin Paleocene. 



15. South rim of Bison basin showing fossil localities. 



16. Two fossil localities in the Bison basin. 



Figures 



Page 



1. Map of western Wyoming and portions of adjacent States 5 



2. Histogram of length of Mj of Claenodon 33 



IV 



