F1IASU0L0M YID.E. 
2A4 
and post-orbital process, both of which are almost obsolete in 
Phase. Wombat. The temporal fossae are not bounded, as 
in the last mentioned animal, by two nearly parallel ridges* 
but are continued by a convex tract to the upper surface of 
the cranium : the supra-tympanic depression is much larger. 
The subjoined dimensions of the skulls of the two animals 
under consideration will assist in conveying a more accurate 
idea of the differences of proportion they exhibit. 
P. tat Ifro ns. 
P. I rombnl. 
Inches. Lines. 
Inches. Lines. 
Total length of cranium 
Greatest width, (which is at the pos¬ 
G 
3 
8 
1 
terior part of the zygomatic arch)... 
5 
0 
5 
9 
Length of nasal bones 
2 
0 
2 
11 
Width of ditto behind ... . 
2 
5 
2 
2 
14 44 near the apex 
1 
2 
10 
Length of frontal bones 
2 
5 
> 
Width of ditto between orbits 
2 
9 
2 
6 
* 4 of skull behind orbits, (where 
contracted by the temporal 
fossa;) ... ... ... 
1 
3 
1 
11 
Length of palate ... . 
3 
7 
4 
7 
Width between the nnterior molars ... 
5* 
34 
44 44 posterior ditto ... 
10* 
1 
0J 
" of superior incisor teeth 
9 
9 
Depth of ditto ... ... ... .. 
Distance between incisor teeth (upper 
3 
5 
jaw) and molars ... ... ... 
1 
64 
1 
11 
Total extent of row of molar teeth ... 
1 
9 
2 
14 
Length of lower jaw ... . 
Height in a vertical line dropped from 
4 
4 
5 
11 
coronoid process ... . 
2 
9 
2 
11 
Width of lower incisors . 
6 
8 
Depth of ditto 
3 
34 
