270 0. C. Marsh — Description of Tertiary Artiodactyles. 



The skull in the f rOntal region is broad and flat. The supra- 

 orbital foramina are widely separated, with diverging grooves 

 leading to them from the nasal suture. The upper molars 

 have oblique crowns, with no antero-median cusp. The upper 

 molar teeth are especially characteristic, as seen from those 

 represented natural size, in figure 23 above. The enamel of 

 the crowns is finely wrinkled, and this has suggested the 

 specific name. This feature is seen also in the lower molars, 

 especially in the teeth of animals not fully adult. The lower 

 jaws are slender, and compressed in front, and there is no 

 diastema in the dentition. 



The bones of the skeleton are very hollow. The humerus 

 is perforated above the distal condyle. The ulna is complete. 

 The fibula is also complete, with the distal end much com- 

 pressed. There are four functional digits in the manus, and 

 possibly five. There are four usable digits, also, in the hind 

 feet, with the lateral ones well developed. 



The affinities of this genus, as already stated, appear to be 

 with the Deer family, and it also has some points of resemblance 

 to the Traguloids. 



Miocene Artiodactyles. 



Figure 24. — Upper teeth of Agriomeryx migrans, Marsh ; seen from, below. 

 Two-thirds natural size. 



Agriomeryx migrans, gen. et sp. nov. 



The present genus is most nearly related to Agrioc/mrus, 

 Leidy, and appears to be its direct successor in a higher hori- 

 zon of the Miocene. The two genera may be readily dis- 

 tinguished by the teeth. The older form has four premolars 

 above and below, while Agriomeryx has but three. In figure 

 24 above, the left upper dental series of this species is shown 

 two-thirds natural size. There are no upper incisors in the 

 present genus. The lower jaws contain a full series of teeth, 



