FROM PLEISTOCENE DEPOSITS, NEW SOUTH WALES. 
251 
level of the base of the outer wall to which they are anchylosed. This character 
is also manifested in the mandibular fragment of the Notiosaur. The fossil has been 
broken away from the lower part of the ramus at the level of one of these apertures 
(Plate 12, fig. 1 , cl), and the fracture exposes the common canal (fig. 6, cl, e), which 
was traversed by the mandibular vessel, and the branch leading from that canal to 
open upon the outer surface, in the same relative position to the free margin of the 
outer wall, as in Hydrosaurus. 
And now, it may be asked, why may not the fossil here described, which has clearly 
come from a saurian as large as Megalania, be part of an individual of that extinct 
Australian genus ? 
True it is, that as yet I have received no portion of mandible so associated with the 
rest of the skull of Megalania as to enable me to make the requisite comparison. 
But so much of the skull, with the upper jaw, as has been recovered indicates that 
such jaw was edentulous, sheathed with horn, as in Chelonia,* and could not have 
been opposed to a series of large, mandibular, conical, carnivorous teeth. Such edentu¬ 
lous condition led to the inference that Megalania had been phytiphagous; and, like 
many herbivorous Mammals, it was proved to be provided with formidable horns as 
defensive weapons.t 
In Notioscmrus w r e have evidence of a second form of Lacertian Hep tile of ordinary 
Crocodilian dimensions, so far as these are indicated by the size and number of the 
piercing, lacerating teeth, of which the fossil in question shows samples. 
I have taken the liberty to write to the Geologist of the Department of Mines, 
Sydney, requesting the loan of any other specimens from the Cuddie Springs which 
may have been regarded as Crocodilian. 
Fig. 1. 
Fig. 2. 
Fig. 3. 
Fig. 4. 
Fig. 5. 
Fig. 6. 
Fig. 9. 
Fig. 7. 
Fig. 8. 
Description of the Plate. 
PLATE 12. 
Notioscmrus dentatus. 
Portion of mandible, outside view. 
Ib. 
ib. 
inside view. 
Ib. 
ib. 
upper view. 
Ib. 
ib. 
end view. 
Ib. 
ib. 
vertical section of mandible and tooth-base. 
Ib. 
ib. 
under view. 
Longitudinal slice of mandible and tooth-base, magnified 120 diameters. 
Hydrosaurus gigas. 
Portion of mandible, with two teeth ; outside view. 
Ib. ib. inside view. 
(All the figures, save fig. 9, are of the natural size.) 
* Phil. Trans., 1880, p. 1045. 
t Ib., p. 1048. 
