THE 



AMERICAN JOURNAL OF SCIENCE 



[FOURTH SERIES.] ^^^^ 



OCT 4 1920 



Jtf- &S 



Art. XVIII. — Entelodonts in the Marsh Collection; by 

 Edward Leffingwell Troxell. With Plate III. 



[Contributions from the Othniel Charles Marsh Publication Fund, Peabody 

 Museum, Yale University, New Haven, Connecticut.] 



TABLE OF CONTENTS 



General summary. 



Bibliography. 

 Part I. Morphology and taxonomy. With PL III. 

 Introduction. 



Purpose of the present paper. 



Status of species. 

 The bony processes in relation to the teeth and muscles. 

 Part II. The genus Archceotherium. With Figs. 1-12. 

 Generic characters of Archceotherium. 

 Archceotherium clavus group. 



A. clavus clavus (Marsh). 



A. clavus darbyi, subsp. nov. 



A. sp. ? 



Summary of group. 

 Archceotherium crassum group. 



A. crassum (Marsh). 



Summary of group. 

 Archceotherium marshi group. 



A. marshi, sp. nov. 



Summary of group. 

 Part III. The larger genera and species. With Figs. 13-20. 

 Pelonax potens group. 



P. potens (Marsh) Peterson. 



P. bathrodon (Marsh) Peterson. 



Summary of group. 

 Hegachcerus zygomaticus group. 



M. zygomaticus, gen. et sp. nov. 



Summary of group. 

 Hegachcerus latidens group. 



M. latidens, sp. nov. 



Ammodon leidyanus (Marsh). 



Summary of group. 

 Chcerodon caninus group. 



C. caninus, gen. et sp. nov. 



Summary of group. 



Am. Jour. Sci.— Fourth Series, Vol. L, No. 298.— October, 1920. 

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