42 
PROFESSOR OWEN ON THE EOSSIL MAMMALS OE AUSTRALIA. 
Ill the year 1845 I received from the accomplished and determined, but unfortunate, 
explorer of Australia, Ludwig Leichhardt, a fossil mandibular ramus of a young Noto- 
there, showing the germ of an incisor which, in adult specimens subsequently acquired, 
proved to be a tooth of temporary growth with crown and fang distinct, as in Macropus , 
Eig. 1. 
Inner side of hind half of left mandibular ramus of Nototherium Mitchelli (} nat. size), “ On Extinct Mammals 
of Australia,” Reports of the British Association for the Advancement of Science, vol. for 1844, pi. iv. fig. 3. 
as will be shown in a subsequent part of the present memoir. One of these adult 
specimens included both rami, contributing satisfactory additional evidence of the 
characters of Nototherium Mitchelli. It was part of the series of fossils collected at 
King’s Creek, Darling Downs, in 1845, and transmitted to London by Mr. Benjamin 
Boyd, where it was purchased by the Trustees of the British Museum, along with the 
cranium and lower jaw and other instructive parts of the skeleton of Diprotodon , described 
and figured in Part III. of the present series of Memoirs* *. 
A portion of maxilla with upper molar teeth of Nototherium Mitchelli also formed 
part of this purchased series. 
In 1856 there was discovered in the same locality the skull, wanting the lower jaw, 
of Nototherium Mitchelli. This unique and valuable specimen came into the possession 
of Frederic Neville Isaac, Esq., by whom it was presented to the Australian Museum, 
then in course of formation in Sydney, New South Wales. 
William Sharpe Macleay, Esq., F.R.S., originator of the Quinary System and author 
sockets of the anterior molars and then bifurcating ; the outer and larger division terminating at the mental 
foramen, and an inner and smaller one extending forwards nearer the symphysis, but without any trace of a 
large incisor ” (op. cit. p. 319). 
* Philosophical Transactions, 1870, p. 519. 
