EXPLANATION OF PLATES 



Plate i 



multituberculates and insectivores from the bison basin paleocene 



Fig. I. Cf. Ptilodus montanus Douglass: Left P* (U.S.N.M. No. 20877), lateral 



view. Four times natural size. 

 Fig. 2. Cf. Ectypodus hazcni Jepsen: Left P* (U.S.N.M. No. 20878), lateral 



view. Four times natural size. 

 Fig. 3. Cf. Ectypodus vmscidus Matthew and Granger : Left ramus of mandible 



with Ml (U. of Wyo. No. 11 05), occlusal view. Four times natural size. 

 Fig. 4. Cf. Anconodon russelli (Simpson) : Right ramus of mandible with P* 



(U. of Wyo. No. 1065), lateral view. Four times natural size. 

 Fig. 5. Bisoiialveus hrozmi, new genus and species: Left ramus of mandible 



(U.S.N.M. No. 20928), type specimen, lingual and occlusal views. Four 



times natural size. 

 Fig. 6. Diacondon pearcei, new species: Left ramus of mandible (U.S.N.M. 



No. 20970), type specimen, lingual and occlusal views. Four times natural 



size. 



Plate 2 

 primates and marsupials from the bison basin paleocene 



Figs. I, 2. Pronothodectes, cf. matthcim Gidley: i. Left ramus of mandible 

 (U.S.N.M. No. 20758), lateral and occlusal views; 2, right ramus of man- 

 dible (U. of Wyo. No. 1062), lateral and occlusal views. Three times 

 natural size. 



Fig. 3. Plesiadapis, cf. jodinatus Jepsen: Left ramus of mandible (U.S.N.M. 

 No. 20784), lateral and occlusal views. Three times natural size. 



Figs. 4, 5. Peradcctcs pauli, new species: 4, Left ramus of mandible (U.S.N.M. 

 No. 20879), type specimen, lingual and occlusal views; 5, left ramus of 

 mandible (U.S.N.M. No. 20880), lingual and occlusal views. Four times 

 natural size. 



Fig. 6. Peradectes elegans Matthew and Granger: Right ramus of mandible 

 (U. of Wyo. No. 1 104), lingual and occlusal views. Four times natural size. 



Plate 3 

 pronothodectes from the bison basin paleocene 



Figs. I, 3. Pronothodectes simpsmn, new species : i. Right ramus of mandible 

 (U.S.N.M. No. 20754), type specimen, lateral and occlusal views; 3, right 

 ramus of mandible (U.S.N.M. No. 20770), lateral and occlusal views. Three 

 times natural size. 



Fig. 2. Pronothodectes, cf. simpsoni, new species : Left ramus of mandible 

 (U. of Wyo. No. 1057), lateral and occlusal views. Three times natural 

 size. 



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