188 ON REMAINS OF AN EXTINCT SAURIAN, 
from its fellow, runs forwards over the fore-end of the lachry- 
mal; the anterior extremity of the frontal is depressed by 
the commencement of a third and mesial groove which widens 
and deepens as it enters the furcation of the nasals. The 
rudiment of a preorbital ridge occupies the orbital part of the 
lachrymal, and adjacent angle of the prefrontal—but there is 
nothing to testify clearly that it does not recommence below 
its appareut termination. Assuming the alligatorian relation- 
ship of the animal, we are by this fossil once more directed 
towards caiman as its nearest kin among living forms: jacare 
being eliminated by the absence of interorbital, and alligator by 
that of preorbital ridges. 
CONDYLAR PORTION OF TYMPANIC, Apttrt. 
Pirate XI., Fic. 2. 
By the form of the condyle alone we should be justified in 
separating generically, if not sectionally, the extinct from the 
living species familiar to Australian observers. The outer limb 
of the condyle of C. porosus is strongly convex and considerably 
broader than the inner, and the ligamenta] pit is anterior to the 
fore edge of its lip. In C. johnstoni this limb is less convex 
and its breadth is equal to that of the inner; the ligamental pit 
is in the middle of its surface. The convexity of the outer 
limb of the fossil condyle is comparatively feeble in both the 
transverse and fore and aft direction, its surface is indeed 
flattened near the central hgamental impression; it is also much 
narrower than the inner limb, which has consequently the larger 
instead of the smaller share in the articulating surface. The 
bone is of greater length, posteriorly to its junction with the 
exoccipital, than in either of the recent species—its length is 
equal to its breadth, whereas in C. porosus the length is three- 
fourths, and in johnstoni but two-thirds of the breadth. 
TEETH. 
Piate XIII. 
The slender sharp-edged teeth, of nearly uniform size and 
shape, of the gavials contrast forcibly with the stout rounded 
