PROFESSOR OWEN ON THE GENUS DINORNIS. 383 
ing epitrochanterian ridge(f). In the above differences Dromornis more resembles 
Dromaius. 
The ectotrochanterian surface (Pl. LXII. fig. 2) is slightly concave, bounded above by 
a low arched ridge, from which the rough convex epitrochanterian part of the surface 
ascended to the crowning ridge. In this character Dromornis resembles Dromaius, and 
differs from Dinornis. 
It resembles Dinornis, and differs from Dromaius, in the absence of the pneumatic 
foramen at the hind part of the upper expansion of the femur. This expansion is also 
relatively greater than in Dromaius, and recalls rather that of Dinornis; but the breadth 
of the ectotrochanterian tract (Pl. LXII. fig. 2) is relatively less than in Dinornis gravis, 
and still less than in the exceptionally thick and massive femur of Dinornis elephan- 
topus. The fore part of the upper femoral expansion has had its outer wall crushed in; 
but, in both the cast and the photograph, there is an indication of a rough subcircular 
tract, answering to that which is conspicuous in Dinornis (loc. cit. pl. 43. fig. 1, 7), but 
which is not present in Dromatus. 
The outer crust of the femoral wall has been crushed inwards at the distal third of 
the fore part of the shaft (Pl. LXII. fig. 1, ¢); but the rotular surface seems to have 
been broad and shallow. In the prominence and thick convexity of the fore part of 
the expansion of the outer condyle Dromornis resembles Dinornis rather than Dromaius. 
The transverse extent of the distal end, in proportion to the size of the shaft of the 
femur, is less than in Dinornis, but is greater than in Dromaius. 
The popliteal cavity (Pl. LXIII. fig. 1, z) is oblique, and is deeper and better-defined, 
especially above, than in Dinornis; it is divided from the intercondylar cavity (v) by a 
ridge (w) similar to that in Dinornis, and which I do not find in Dromaius. The inter- 
condylar cavity or pit (v) is deep, and smaller than in Dinornis gravis; it is deeper, but 
much smaller, than in Dinornis elephantopus (loc. cit. pl. 43. fig. 3). There is a rough 
“luteal” depression (Pl. LXIII. fig. 1, 2), less deep than in Dinornis gravis, and 
situated nearer the popliteal cavity, and with a more posterior aspect than in Dinornis 
elephantopus. 
The mutilation of the prominent parts of both femoral condyles precludes further 
profitable comparisons of the fossil under consideration. 
But from those for which it affords sufficient grounds, I infer that in its essential 
characters this femur resembles more that bone in the Emu than in the Moa, and that 
the characters in which it more resembles Dinornis are concomitant with, and related 
to, the more general strength and robustness of the bone—from which we may infer 
that the species manifested dinornithic strength and proportions of the hind limbs, 
combined with characters of closer affinity to the existing smaller, more slender-limbed, 
and swifter wingless bird peculiar to the Australian continent’, 
1 I can now, in 1872, repeat with more confidence the remark in my Memoir of 1846:—* No remnant of a 
Dinornis has yet been found in any of the contiguous islands; and I have in vain searched for such in the col- 
lections of post-pliocene fossils from Australia.”—Trans. Zool. Soc. vol. iii. p. 366. 
