384

354

on the first received collection of bones from New Zealand 1. But the femur of the Emu
(Dromaius), though still smaller than that of the Ostrich in comparison with the
gigantic species of Dinornis, is less different in shape. The shaft of the bone is
rounder than in the Ostrich ; but the antero-posterior diameter of that part is less
than in Dinornis. There is no trace of the bifurcate ridge on the fore part of the
shaft, and very feeble indications of "lineae asperae" on the back part ; of the tuber-
rosities there developed in Dinornis no rudiment even is present in existing Stru-
thionidae. The medullartierial canal is very minute in Dromaius, as in other pneumatic
femora ; and the associated large air-hole at the back part of the upper end of the
femur significantly differentiates Dromaius, as it does the other large existing Stru-
thionidae, from Dinornis. The head is sessile ; one cannot predicate a cervix in the
femur of Dromaius ; the trochanter hardly rises above the level of the head ; the
back of the trochanter is scarcely at all accentuated, chiefly shows a smooth, feeble
concavity ; there are no gluteal rugosities, no trace of a lesser trochanterian place of
muscular attachment. The popliteal cavity is a shallow groove, not bounded by any
post-intercondylar ridge from the intercondylar space. The distal expansion is rela-
tively much less than in Dinornis ; the inner condyle is much narrower. The tibial
part of the outer condyle has relatively more longitudinal extent in Dromaius than in
Dinornis, where it equals in that dimension the tibial prominence. But the fibular
division projects more outwardly in Dromaius, is broader in proportion to its length,
and more generally convex. There is no trace of the rough pit for ligamentous or
muscular attachment above the fibular division of the outer condyle which so markedly
distinguishes the femur of Dinornis.

The antero-posterior extent of the outer condyle is much greater than that of the
inner condyle in Dromaius ; the difference is less in Dinornis giganteus 2, Din. casua-
rinus 3, and Din. didiformis 4. the antero-posterior dimension of the outer and of the
inner condyle are nearly the same in Dinornis gravis.

The pelvis of Dinornis gravis is characteristically massive and ponderous, and accords
in shape with those figured in Plates XIX. & XX. of the first Memoir 5.

The upper and outer bony wall of the hinder expansion, beyond the gluteal ridges,
is better preserved than in figure 3, Plate XX.

Eight coalesced vertebrae with combined par- and pleur-apophyses precede the three
interacetabular vertebrae, in which those processes are wanting. The bodies of these
are broader and flatter below then in the subject of figure 2, Pl. XIX. After the
above eleven sacrals follow six vertebrae with par- and pleurpophyses again abutting
against the iliac walls.

The first sacral has, on each side the centrum, a circular cup for the head of a free

1 Ante, p. 73 2 Pl. XXXVI. fig. 2. 3 Pl. XXXVIII. fig. 3.
4 Pl. XXIV. fig. 3. 5 Anter, p. 73.