PROFESSOR OWEN ON THE FOSSIL MAMMALS OF AUSTRALIA. 
209 
Macropus major. Macropus Titan. 
in. lines. in. lines. 
From lower border of orbit to alveolar border atwi .10 16 
Length of series of four molars (d 4. to m z) 1 10 2 2 
Length of m 2 and ms 11 13 
Breadth of fore lobe of m 3 0 4| 0 6 
§ 9. Macropus Titan (Femur). — An almost entire thigh-bone, in the same petrified 
condition as the skull above described, and from the same freshwater drift in King’s 
Creek, offers the same proportions to that skull and to the mandible and teeth of 
Macropus Titan as the femur of Macropus major does to the same parts in that species. 
It is of the right side, in length 11 inches 6 lines; but would equal, if not exceed, a 
foot in length were the summit of the great trochanter entire. The bone is figured, of 
the natural size, in Plate 27, 2-| inches of the middle of the shaft being omitted in 
figs. 1 and 2 to bring them into the quarto form. The macropodal characters of this 
fine fossil femur, and the deviations, besides size, from the femur of the largest existing 
Kangaroos, will be readily appreciated if Plate 27 be compared with plate lxxxi. Zool. 
Trans. * of the femur of Macropus ( Osphranter ) rufus. 
A trace of the antero-internal groove, defining in that recent species the super- 
trochanterian tuberosity, is plain in the fossil at e, figs. 1 & 2, Plate 27, where 
that tuberosity has been broken away. Compared with the femur of Macropus rufus 
that of Macropus Titan shows a relatively wider and shallower concavity (ib. fig. 1, d) 
between the fore part of the great trochanter and the head (a) of the bone. The 
“ cervix femoris ” ( b ) is relatively thicker. The transverse diameter below the head is 
relatively greater, mainly through the greater extent of the bone internal to the 
“ small trochanter ” (ib. fig. 2, n), whereby that outstanding ridge-like process does 
not appear in a direct front view (ib. fig. 1). The same relative position of n in the 
femur of Palorchestes Azael is also due to the inward extension of the support of the 
neck and head of the bone. 
The femoral shaft in Macropus Titan is relatively thicker, especially from before 
backward, than in Macro'pus major and Macr. rufus. The rough depression (ib. 
fig. 4, y ) above the outer condyle is relatively larger, deeper, more sharply defined. 
The inner condyle (ib. figs. 1 & 2, t) has its inner (tibial) border better defined and 
produced so as to give a slight concavity, transversely, to that half of the back part 
of the condyle. This character is more marked in Palorchestes (Plate 23. fig. 2, t) ; 
but there is no trace of it in the inner femoral condyle of the large existing Kangaroos. 
The intercondylar notch (u, fig. 2, Plate 27) is narrower and deeper in Macropus Titan 
than in Macropus rufus, again repeating a femoral character of Palorchestes , but not 
in so marked a degree. The ectocondylar pit (ib. fig. 4, v) is equally well marked. 
The broad shallow vertical groove at the back part of the outer condyle, which in 
Macropodidce offers so interesting an approach to the characteristic structure of that 
* Yol. ix. 
