484 THE STRUCTURE AND RELATIONSHIPS OF ANCODUS. 
tracted, much narrower than on the plantar side. The proximaUacets are of un- 
e(|nal size, that for the calcaneuin being considerably the wider. The latter is con- 
vex antero-postoriorly and is broad behind, narrowing toward the front, descending 
lower upon the dorsal Dice than in the specimens figured by Kowalevsky (FI. 
XXX VI 11, fig. 1), and separated by a distinct groove from the ascending process 
which forms °the astragalar facet. The latter surface is divided into two facets, 
dorsal and plantar, widely separated by a broad and deep sulcus. The plantar 
surface of the cuboid is very broad and, in general, agrees with the shape found in 
the European sjiecies, though dillering in some details. Kowalevsky says of Ins 
specimens: “Looking at the cuboid from the posterior aspect, we perceive a very 
broad and rough transverse ridge for muscular and ligamentous attachment, running 
through the whole breadth of the bone. . . . This ridge does not reach the 
level of the distal articular surface of the cuboid, which is the lowmst point of the 
bone” (p. 57). “ Instead of the broad transverse ridge seen on the posterior sur- 
face of the cuboid in the Hyopotarnus, the cuboid of the two-toed Diplopus has this 
ridge prolonged downward in a beak-like process quite of the same shape as in the 
common Hog. This posterior beak descends lower down than the distal articular 
surface of the cuboid, and exhibits on its inner side an elongated facet, by which 
this beak articulates with a corresponding cuboid facet on the outer side of the 
posterior prolongation of the fourth metatarsal. ... In my specimens of 
Hyopotarnus from Puy the posterior prolongation of mt. IV is not well preserved ; 
but as there is no downward prolongation on the cuboid and no facet, the cuboid 
seems not to have articulated with this posterior prolongation of the fourth meta- 
tarsal, and it does not so articulate in Anoplotherium and Hippopotamus” 
(pp. 58-59). 
In A. brachyrhynchus there is a very massive but rather short posterior beak 
which does articulate with the posterior prolongation of mt. IV, just as Kowalevsky 
describes it in Diplopus, but internal to this the broad transverse ridge extends beneath 
nearly the entire breadth of the navicular and above the posterior hook of mt. Ill, 
and has a broad contact with the entocuneiform. On the tibial side the cuboid 
displays two large facets for the navicular, which are separated by a continuation 
of the same wide and deep sulcus that divides the astragalar facet into two parts. 
The dorsal navicular facet presents internally, the plantar one superiorly. The 
distal facets for the metatarsals do not dilfer notably from those of the European 
species. 
In Oreodon the cuboid is relatively lower and broader than in Ancodus ; the 
calcaneal facet is not cut so deeply into the anterior face, and the astragalar facet 
IS continuous, not being divided by a sulcus. The posterior beak is rudimentary 
.7 r“, is excluded fram any 
between tliei ri w f e t*eak of the navicular, which intervenes 
“■““'I'-' ‘tan in 
The mvicular is high and rather narrow, its greatest diameter being the antero- 
