. On the anatomy of vertebrates [electronic resource] . adius is remote from that which joinsthe trapezium, t, and trapezoides, d. The single surface of thepisiforme has two facets, the smaller of which joins the trapezium extends along half the metacarpal of the phalanges, two in the first and three in each of the otherfour digits, are broad and short, especially the last, which isfirmly encased in the corresponding division of the hoof. The hind limbs and pelvic arch present opposite proportions tothose in the Megatherioids : the skeleton of the extinct Probos-cidian leaf-
. On the anatomy of vertebrates [electronic resource] . adius is remote from that which joinsthe trapezium, t, and trapezoides, d. The single surface of thepisiforme has two facets, the smaller of which joins the trapezium extends along half the metacarpal of the phalanges, two in the first and three in each of the otherfour digits, are broad and short, especially the last, which isfirmly encased in the corresponding division of the hoof. The hind limbs and pelvic arch present opposite proportions tothose in the Megatherioids : the skeleton of the extinct Probos-cidian leaf-eater, fig. 297, contrasts singularly in this respectwith that of the extinct Megatherioid one, fig. 267. To boththese giants among land quadrupeds the forests of the primevalworld afforded sustenance ; but their ways of obtaining it weredifferent, and called for preponderance of developement in thehind part of the skeleton in the one, and of the fore part in theother. The pelvis descends vertically at almost a right angle SKELETON OF PROBOSCIDIA. 443. Pelvis of the Elephant, front view. with the trunk, fig. 162, 62, the ilia forming with the lumbarseries an angle of 120°: the ischium and pubis are short, andform a symphysis, fig. 298, g, the axis of which runs at an angleof 100° with that of the ilium. This bone arches out from itssacral joint almost transversely, the thick rough crista descendingwith its angle, a, produced to a level with the acetabulum : theanterior or abdominal surface is concave. The ischium, jf, hasthe tuberosity, e, directed ^gdorsad: the pubis showsa pectineal ridge, h. Thesciatic notches are widelyopen: the obturator fora-mina are smaller than theacetabula, the planes ofwhich incline from the per-pendicular about 70°, — afavourable position for trans-mitting the weight uponthe heads of the femora:these, as in the Megathere,have no round ligament, andthe acetabulum is simplifiedaccordingly. In a young Elephant I have observed an accessorypelvic oss
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