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ridge (ib, g) commencing at the inner side of the shaft, one inch below the neck. The 
two oblique ridges are divided by a smooth interspace 4 lines in breadth, below 
which is the orifice of the medullary artery (ib. 7). On each side of this orifice the 
line aspere are, as it were, resumed, and descend slightly diverging,—the outer one 
(ib. p') gradually subsiding near the ectocondylar pit (£); the inner one (ib, g) descends 
an inch and a half below the arterial orifice to form the tuberosity, g'. Internal to 
this rises a second rough tuberosity (ib. g”), continued by a ridge to within an inch of 
the hind angle of the inner condyle (ib. w). 
From the ectotrochanterian tuberosity (Pl, XLI. fig. 1, 7) the strong ridge bisecting 
the fore part of the mid third of the shaft is continued down near the mid line of that 
surface. Six inches below the upper end of the femur this ridge, which divided the 
attachments of the “ vastus externus” and “ vastus internus” muscles, bifurcates, its 
divisions diverging to the upper end of the condylar risings (ib, wu, y), but subsiding 
before attaining these. 
At the lower part of the pretrochanterian surface, midway between the head and the 
ectotrochanterian tuberosity, is the rough surface, partly prominent, partly depressed 
(Plate XLI. fig. 1, s), which seems to represent the small trochanter in Mammals. 
The rotular cavity or channel (ib. fig, 1, #), 2 inches across and 14 inch in depth, 
shows no trace of the rising marked in that part of the femur of Dinornis giganteus'. 
‘The anterior intercondylar ridge dividing the rotular fossa (¢) from the intercondylar 
one (Pl, XLI. a. fig. 1, v, v') is sharp, The intercondylar fossa is partially divided into 
two depressions, the inner one (ib. v) being the deepest, the outer one (v’) the largest. 
These are divided from the popliteal cavity (Pl. XLI. a, fig. 1, z) by the post-intercon- 
dylar ridge (ib. w), which is well marked, but shorter, thicker, and more rounded than 
the anterior one (Pl. XLI. fig. 2, #’). 
The entocondylar articular surface (ib. w') has the usual relative size and shape’. 
The ectocondylar surface for the tibia (ib. #) is comparatively small, measuring 
L inch 9 lines by 1 inch in extent; it is continued over the ridge-like posterior pro- 
jection of this part of the condyle to that on the concavity or groove for the head of 
the fibula (Pl. XLIL. . fig. 1, 7), which groove is feebly divided into an upper (y') and 
lower (y") tract. 
The popliteal space (ib. fig. 1, 2) has the usual dinornithie depth, shape, size, and 
oblique direction. It is rugous; and some small foramina at its deepest part are the 
sole representatives of a pneumatic system, though probably related only to the trans- 
mission of vessels. 
The contrast is striking, in placing by the side of the above-described bone the temur 
of any of the species of large existing Struthious birds, in regard to every indication of 
the strength and vigour of application of the hind limbs. The chief results of the 
comparison of the femur of Dinornis with that of Struthio were recorded in the Memoir 
1 Pl, XXXVI. fig. 2, r. 2 Pl. XXXVIIL fig. 3, ¢ (Dinornis casuarinus), 
