Scott.] 218 [May 18, 



incised, (o) The fibular facet of the calcaneum is higher and more 

 oblique, but less extended antero-posteriorly. (6) The calcaneal facet of 

 the cuboid is relatively broader, while that for the astragalus is narrower. 

 Uiifortuuately the compound cuneiform is lost from the specimens of 

 A. nntiquus and the only navicular preserved is too much injured for com- 

 parison. 



The tarsus o( AgriocJicerus is fundamentally similar to that of Oreodon, 

 but with many significant differences of detail. Comparing 0. culbertsoni 

 with A. antiquum the following deviations in the structure of the latter 

 may be observed. (1) All the tarsal bones are much lower and broader. 

 (2) The pit on the astragalus for the tibial malleolus is much deeper and 

 the ridge separating the cuboid and navicular facet of this bone is decidedly 

 more prominent. (3) The sustentaculum of the calcaneum is much more 

 strongly developed and projecting. (4) The calcaneal facet descends 

 lower upon the dorsal face of the cuboid ; the hook-like process on the 

 plantar surface of the cuboid is very much more massive and the distal 

 facet for the fifth metatarsal less distinctly separated from that for the 

 fourth. In A. gaudryi the plantar book of the navicular is greatly in- 

 creased in breadth as compared with that of 0. culbertxoni, and on the 

 distal surface of the compound cuneiform the facets for the second and 

 third metatarsals lie in the same transverse plane, instead of being at dif- 

 ferent levels. In consequence of this arrangement the second metatarsal, 

 which in Oreodon abuts against the tibial side of the ectocuneiform, is en- 

 tirely' excluded from that element. Whether the same is true of A. 

 antiquus cannot at present be determined. In one of the specimens of the 

 latter species the entocuneiform is preserved. It is considerably wider 

 than the same bone in Oreodon, and has a distal facet for the first meta- 

 tarsal, thus confirming Osborn and Wortman's observation as to the 

 presence of a hallux in this genus. A number of caudal vertebrae show 

 that Agricchcerus had a longer and more powerful tail than Oreodon; in- 

 deed, the tail is quite as well developed as in the larger cats, e. g., th« 

 leopard. I have elsewhere called attention to the curious character of the 

 axis in this genus {Morphologiaches Jahrbuch, Bd. xvi, p. 3G1). The 

 odontoid process has the characteristic shape found in the oreodonts ; it is 

 short and bro id, with strongly convex ventral surface, nearly flat dorsal 

 surface, and rounded anterior margin. This process is, therefore, neither 

 conical nor spout-shaped, but intermediate between the two. The neural 

 spine, on the other hand, is entirely difterent from that of the oreodonts 

 and forms a great hatchet-shaped plate, resembling carnivorous rather than 

 ungulate structure. 



The Systematic Position of Agkiochcekus. 



Leidy separated this genus from the oreodonts, as the type of a distinct 

 family, which he regards as a " peculiar and extinct family of ruminants 

 of the most aberrant character, but allied to the Oreodonts." Gill united 

 the two families, gw'mgio Agriochoirus subfamily rank, an example which 



