98 



ON MEOALANIA AND ITS ALLIED, 



testified by a tooth which though it stands alone, can hardly lead 

 to a misapprehension of its generic origin. We may refer to it 

 under the name of Varanus dirus. 



With rare exceptions, living representatives of the genus have- 

 their teetli more or less compressed, and generally reduced to an 

 edge on the caudal aspect. In the fossil tooth this compression 

 is carried to an unusual extent — on the ental side, indeed, the cusp- 

 is flat and, above the middle of the base, even impressed in the- 

 centre : on this side there are but four feeble ribs, bifurcating as 

 usual as they approach the base, on which is a cingulum surmounting 

 the line of attachment to the jaw ; on the outer side the cusp is 

 moderately convex and conspicuously ribbed. The ribs resulting 

 from the confluence of pairs, which in this case cover the basal two- 

 fifths of the crown, in their upward course follow the sinuous 

 contour of the tooth, and are traceable nearly to the apex. The- 

 serration of the acute caudal edge is distinct and regular, and 

 passing over the apex extends upon nearly a third part of the- 

 rostral margin. The whole tooth has a graceful sigmoid curve 

 caudad. Its height and breadth at the base are thrice those of a 

 corresponding tootli of V. varius — wherefore, on the assumption of 

 like proportions throughout, it represents a Varan of about sixteen 

 feet in length. 



An imperfect distal end of a young femur wanting the- 

 epiphysis may be provisionally ref. rred to this species. 



The hypothesis that the disappearance of the old fauna of 

 Australia was caused by human agency does not seem to be favoured 

 by the fact that it included three such reptiles as Megalania r 

 Notiosauius, and Varanus dirus ; it is hardly probable that the 

 forefathers of Australian natives, as we know them, were men able 

 to cope with aggressors as numerous as the remains as Megalania 

 alone prove them to have been. 

 Varanus emeritus. 



The lacertian remains, so named, consist of portions of a 

 humerus and tibia. In the humerus, which wants the proximal 

 end from the latissimus dorsi insertion exclusive, the family 



