10 
THE UPNOR ELEPHANT 
The Trapezoid (PL IV, figs. 4 a, 4 b ). — The proximal surface of the trapezoid, 
which forms the facet for the scaphoid, is nearly flat, and is triangular in outline. 
Probably a very narrow strip of the anterior portion of the edge next to the 
magnum was overlapped by the lunar, but no special facet is developed. The 
facet for the trapezium is deep in front and narrow behind, a deep pit occurring 
at the junction of the broad and narrow portions. The facet for the magnum 
is nearly divided into a deep anterior portion and a narrow posterior one. The 
distal facet for union with the second metacarpal is gently convex in all directions ; 
it is narrow posteriorly, but widens out towards the front, where it covers the whole 
width of the upper end of the metacarpal II, which is thus entirely shut out in front 
from any contact with the magnum. In most elephants, as will be shown below, 
the magnum has an articulation with the second metacarpal extending from the 
front to the back of the bone. 
The dimensions of the trapezoid are : 
mm. 
Greatest width of the outer (postaxial) border . . . . . . 146 
Long diameter of the facet for the scaphoid . . . . . . 112 
Width of the inner (preaxial) face . . . . . . . . . . 114 
Width of outer (volar) face . . . . . . . . . . . . 98 
Height of outer (volar) face . . . . . . . . . . . . 8 
The Magnum (PI. V, figs. 1 a, 2 a ). — This bone is preserved on both sides. 
Its upper articular surface is almost exactly as in E. africanus. In the articulated 
foot it is completely covered anteriorly by the distal surface of the lunar which 
projects a little beyond it, both on the outer and inner sides. Posteriorly, as noted 
above, the lunar narrows so that the postero-internal and postero-external angles 
of the upper surface of the magnum are left free to articulate with the scaphoid and 
cuneiform respectively. The surfaces for articulation with the trapezoid and 
unciform are almost exactly like those occurring in E. africanus, but the distal 
(metacarpal) surface is peculiar. In nearly all the other species in which the 
magnum is known, the facet for union with the second metacarpal extends to the 
front of the bone and makes an obtuse angle with the facet for the third meta- 
carpal ; it is usually much narrower than this latter, though in one specimen of 
a magnum dredged up at Happisburgh (perhaps belonging to E. meridionalis) the 
facets for the second and third metacarpals are of nearly equal width and make 
an angle of about 120° with one another. In our specimen (PI. VIII, fig. 2 a, me. 2), 
the facet for the second metacarpal is confined to the posterior portion of the 
bone, while that for the third widens anteriorly, so that there it occupies the 
whole width of the bone, and when looked at from the front the magnum seems 
to have to carry the third metacarpal only and to have no contact with the second. 
The only other specimens I have been able to find showing this arrangement 
of the facets belong to undetermined Siwalik (probably Pliocene) species. One of 
these is a single bone (17457), the other is included in a carpus (M3195) figured 
by Falconer in Fauna Antiqua Sivalensis (PI. 50, fig. 1). In another carpus 
