24 AGRIOCHOERUS. 



Inches. Lines. 



Height of lower jaw at first temporary premolar 7 



Height of angular apophysis 10 



Distance from coronoid process to anterior mental foramen .... 4 4 



Length of upper series of six molars 2 6 



Length of lower series of six molars 2 8 



GRE.\TEST DIAMETER. 



Antero-posterior. Transverse. 



Seventh upper molar ......... 7 lines. 6 lines. 



Sixth upper molar 6* " 5i 



Fifth upper molar 5J " 5 



Third temporary molar ........ 5 " 4 



Second temporary molar ........ 5 3 



First temporary molar . . . . . . . . 4i " 1 



First permanent premolar . . . . . . . . 3J " 1 



Seventh lower molar ......... 9 " Si- 

 Sixth lower molar . . . . . . . . . 6i " 



Fifth lower molar . . . . . . . . . 5J " 



Third temporary molar . . . . . . . . 6 " 2} " 



Second temporary molar . . . . . . . . 5 " li " 



First temporary molar ........ 4 " 1 " 



AGRIOCHOERUS, Leidt. 

 Agrioclioei'ii!^ aiiti(|uiis, Leidy. 



(Plate I. Figs. 5-10.) 

 Af/riochoerus aniicpms, Leidy: Proo. Acad. Nat. Sci., 1850, V. 121; Owen's Rep. of a Geol. Surv. ofWisc., etc., 571. 



AgriocJioerus is a remarkable and very peculiar genus of ungulata, representing 

 a type which occupies a position in the wide physiological interval existing between 

 recent ruminants and the anomalous Anoplotherium. 



It was first established in the Proceedings of the Academy of Natural Sciences 

 of Philadelphia, for 1850, upon a portion of a skull, and several fragments of jaws 

 with teeth, received from my friend. Dr. Hiram A. Prout, of St. Louis. 



Of the species characterized under the name of AgriocJioerus antiqmcs, I have 

 had the opportunity of studying the following specimens : — 



1. A much mutilated face, with the forehead, and portions of both sides of the 

 lower jaw, apparently of an adult individual. The ui3per jaw contains upon one 

 side the posterior five molars, and upon the other side the posterior si.K molars. 

 Both fragments of the lower jaw contain the posterior five molars. The first true 

 molar is only slightly worn, while the others have hardly yet been affected by 

 trituration. Eeceived from Dr. Prout. (PI. I., Figs. 5-8.) 



2. Two fragments of the upper maxillae, containing each the last two true molars, 

 and a fragment of the lower jaw containing the anterior two true molars. These 

 apparently belonged to the same and an older individual than the former. Received 

 from Dr. Prout. (Pigs. 9, 10.) 



Description of the portion of a Skull. — Viewed from above, the anterior portion of 

 the skull is nearly equilateral triangular, the sides of the face converging in a nearly 



