PETERSON: A REVISION OF THE ENTELODONTID® 135 
but at right angles, and are quite similar to those in Sus and Hippopotamus. The 
unusual dorso-plantar extent of the distal facet for the astragalusin Archxotherium, 
which was pointed out by Scott, isin Dinohyus fully as great. The latter facet is 
confluent with the lateral facets for the cuboid, and only separated from the distal 
facet for the same bone by a rounded angle, which is confined to the anterior half 
of the distal facet. The distal facet for the cuboid is divided into two parts: an 
anterior, which is plane; and a posterior, which is obliquely concave antero-pos- 
teriorly, and is carried high up upon the tibial face to accommodate the corre- 
sponding facet of the prominent plantar hook of the cuboid. Above the cuboid and 
distal astragalar facets there is on the fibular face a deep excavation, which is 
bounded superiorly by the fibular and sustentacular facets and posteriorly by the | 
heavy border of the tuberosity. The sustentacular facet is quite large and is slightly 
conyex transversely and concave in the dorso-palmar direction. 
MEASUREMENTS OF CALCANEUM. 
Greatest length. ovis catecseteaster es seetenccces catessuos na imesoose gst aaee cceeramaueaera te 
Length of tuber... 
Greatest antero-posterior diameter at fibular facet..............00. cesesseeeeeeee ers 82 
Me transverse diameter at sustentacular facet...............:.sceseereeereeees 60 
Navicular. —The proportions of the navicular are different from those in the 
Oligocene genus, which fact is due to the relatively smaller transverse and greater 
antero-posterior diameters in Dinohyus. The articulation for the astragalus is 
divided by a broad rounded ridge, which is evenly 
convex from side to side, deeply concave an- 
tero-posteriorly, and terminates in elevated and 
rounded borders dorsally and palmarly. The 
fibular portion of the astragalar facet is rapidly 
deflexed externally and terminates abruptly at 
the fibular angle, while the tibial portion is gently 
concave transversely and greatly concaye antero- 
posteriorly. The fibular face has three facets for 
the cuboid, two dorsal and one palmar, as in Fig. 791) Distal View of Tarsus of Lett 
1 
Archxotherium. There is apparently a tendency Pes of Type of D. hollandi Peterson. 4 nat. 
reecrs : : size. facet. He = ecto- iform. Mc 
toward codssification between the navicular and oe Gi eens 
mesocuneiform. 
cuboid, as the articulating facets are reduced and 
the surfaces very rugose throughout. The dorsal face is plane except the rugose and 
sharp fibular angle which abuts against the cuboid. On the anterior portion of the 
tibial face the bone is convex vertically, and more so posteriorly. This convex por- 
tion is suddenly succeeded by a prominent and rugose area for muscular attachments. 
