Peterson: Miocene Beds of Nebraska and Wyoming. 41 



the astralagus has a fore and aft position very like that in Merychyus. 

 The fibula had a complete shaft, judging from the comparatively 

 large fragment adhering to the shaft of the tibia. 



The astragalus and the cuboid are high. The navicular and cal- 

 caneal facets of the cuboid are very nearly of equal size. The facet 

 on the cuboid accommodating metatarsal five is located on the tibial 

 side of a small lip on the outer angle, which extends below the artic- 

 ular facet for the fourth metatarsal. The palmar hook of the cuboid 

 is quite robust. The navicular and cuneiform are injured by erosion, 

 but enough of them is preserved to show their close similarity to the 

 corresponding bones in Merychyus. The second and fifth metatarsals 

 are relatively longer than in Merychyus minimus and not nearly so 

 heavy as those in Phenacocoelus typus. In comparing the second 

 metatarsal (which is broken off at the distal epiphysis) with the cor- 

 responding bone of Merychyus minimus (No. 1331, Car. Mus. Cat. 

 Vert. Foss. ) it is seen that while the bones are of the same length the 

 one here described is much the heavier of the two. It is also notice- 

 able that metatarsals three and four are proportionally smaller than 

 those in Merychyus minimus, and, when complete, no doubt they would 

 be shorter. The proximal articulation of metatarsal five is very small 

 and fits neatly into the overhanging lip on the fibular angle of the cuboid 



referred to above. 



Measurements. 



mm. 



Total length of the fragment of the tibia 127 



Transverse diameter of distal end of tibia 19 



Antero-posterior diameter of distal end of tibia 14 



Greatest height of astragalus 25 



Greatest transverse diameter of astragalus 14 



Vertical diameter of cuboid, anteriorly 15 



Transverse diameter of cuboid, anteriorly 9 



Vertical diameter of navicular, anteriorly 8 



Vertical diameter of ecto-meso-cuneiforms 6 



Transverse diameter of tarsus at head of metatarsals 19 



Length of metatarsal II from proximal end to epiphysis of distal end. .. 44 



Stenomylus gracilis, gen. et sp. no v. 



(Plate XII.) 



(Type. No. 1610, Cam. Mus. Cat. Vert. oss. 



This remarkable cameloid form was found by the writer in the 

 Lower Harrison beds on the Niobrara (Running Water) River, Sioux 



