268 
POPULAR SCIENCE REVIEW. 
Thomas Mitchell, and which are described and figured in the 
“ Appendix ” to his “ Three Expeditions into the Interior of 
Eastern Australia” (2 vols. 8vo. 1838) was the fore-end of 
one-half of a lower jaw with the implanted end of a fractured 
tusk. It indicated a beast as big as a hippopotamus. This 
fossil and a limb-bone, sent to Paris, of what I subsequently 
determined to belong to the same species, had given rise to the 
notion that a true hippopotamus and an elephant had left their 
remains in the caves and drift deposits of Australia.* 
After an extensive and minute comparison of the tooth-stump 
from Wellington Valley with every quadruped of similar size 
having such a tusk at the fore part of the under jaw, I came to 
the conclusion that it must have belonged to a distinct kind of 
animal ; that the tusk had been one of a pair like the lower 
incisors in the kangaroos, wombats, and phalangers ; and that 
the fossil, therefore, indicated the former existence in Australia 
of a marsupial quadruped as big as a rhinoceros or hippopotamus ; 
but, being of a distinct genus and species, I described and 
figured it as representing a new form — Diprotodon australis. 
But what would this problematical Diprotodon , guessed at by 
a bit of a tooth, turn out to be ? 
Now, here I may remark that there is no chase in the sporting 
world so exciting, so replete with interest, so satisfactory, when 
events prove one to have been on the right scent, as that of a 
huge beast which no mortal eye will ever see alive, and which, 
perhaps, none ever did behold ! 
Such a chase is not ended in a day, a week, or a season. 
One’s interest is revived and roused year by year as bit by bit 
of the petrified portions of the skeleton come to hand, and 
thirty such years elapsed ere I was able to outline a restoration 
of Diprotodon australis such as is shown in the plate of the 
workf now submitted to the Institute. 
The dental formula of the Diprotodon is that of the notothere 
. 3—3 0-0 
and of the kangaroo, namely, i — c — — , 
m 
5-5 
5-5’ 
28. 
The true molars have the crown cleft into two strong transverse- 
ridges, also the fundamental pattern of those teeth in the 
kangaroos. But the skull of the Diprotodon is a yard in 
length.^ The thigh-bone might well suggest to the Parisian 
palaeontologist the idea of an elephantine quadruped. The fore 
limbs and hind limbs are of equal length. The animal must 
* See Lyell, “ Principles of Geology,” 8vo. ed. 1835, p. 143. 
t “Researches on the Fossil Remains of the Extinct Mammals of 
Australia : with a Notice of the Extinct Marsupials of England.” 4to. 2 vols. 
1877. (Erxleben, 2 Henrietta Street, Brunswick Square.) 
X See Frontispiece of the above work. 
