INTRODUCTION. 
xm 
Professor Owen states — “ Australia yields evidence of an analogous correspondence between its last extinct 
and its present aboriginal mammalian fauna, wbicb is the more interesting on account of the very peculiar 
organization of most of the native quadrupeds of that division of the globe. That the Marsupialia form one 
great natural group is now generally admitted by zoologists ; the representatives in that group of many of 
the orders of the more exclusive Placental subclass of the Mammalia of the larger continents have also been 
recognized in the existing genera and species : the Dasyures, for example, play the parts of the Carnivora ; 
the Bandicoots ( Perameles ), of the Insectivora ; the Phalangers, of the Quadrumana ; the Wombat, of the 
Rodentia ; and the Kangaroos, in a remoter degree, of the Ruminantia. The first collection of mammalian 
fossils from the ossiferous caves of Australia brought to light the former existence on that continent of 
larger species of the same peculiar marsupial genera : some, as the Thylacine, and the Dasyurine subgenus 
represented by the D. ursinus, are now extinct on the Australian continent ; hut one species of each still 
exists on the adjacent island of Tasmania; the rest were extinct Wombats, Phalangers, Potoroos, and 
Kangaroos — some of the latter (. Macropus Atlas , M. Titan ) being of great stature. A single tooth, in the 
same collection of fossils, gave the first indication of the former existence of a type of the Marsupial group, 
which represented the Pachyderms of the larger continents, and which seems now to have disappeared 
from the face of the Australian earth, — of the great quadruped, so indicated under the name of Diprotodon 
in 1838 ; and successive subsequent acquisitions have established the true marsupial character and the near 
affinities of the genus to the Kangaroo ( Macropus ), but with an osculant relationship with the herbivorous 
Wombat. The entire skull of the Diprotodon , lately acquired by the British Museum, shows in situ the 
tooth on which the genus was founded. This skull measures 3 feet in length, and exemplifies by its size 
the huge dimensions of the primeval Kangaroo. Like the contemporary gigantic Sloth in South America, 
the Diprotodon of Australia, while retaining the dental formula of its living homologue, shows great and 
remarkable modifications of its limbs. The hind pair were much shortened and strengthened compared 
with those of the Kangaroo ; the fore pair were lengthened, as well as strengthened. Yet, as in the case of 
the Megatherium , the ulna and radius were maintained free, and so articulated as to give the fore paw the 
rotatory actions. These, in Diprotodon , would be needed, as in the herbivorous Kangaroo, by the economy 
of the marsupial pouch. The dental formula of Diprotodon was the same as in Macropus major : the first of 
the grinding series was soon shed, but the other four two-ridged teeth were longer retained ; and the front 
upper incisor was very large and scalpriforin, as in the Wombat. The zygomatic arch sent down a process 
for augmenting the origin of the masseter muscle, as in the Kangaroo. The foregoing skull, with parts of 
the skeleton of the Diprotodon australis, were discovered in a lacustrine deposit, probably pleistocene, 
intersected by creeks, in the plains of Darling Downs, Australia. 
“ The same formation has yielded evidence of a somewhat smaller extinct herbivorous genus ( Nototherium ), 
combining, with essential affinities to Macropus, some of the characters of the Koala {Phascolarctos). The 
writer has recently communicated descriptions and figures of the entire skull of the Nototherium Mitchelli to 
the Geological Society of London. The genus Phascolomys was at the same period represented by a Wombat 
(P. gigas) of the magnitude of a Tapir. The pleistocene marsupial Carnivora presented the usual relations 
of size and power to the Herbivora whose undue increase they had to check.” 
In another work, Prof. Owen represents an almost entire skull, with part of the lower jaw, of an animal 
( Tliylacoleo ) rivalling the Lion in size, the marsupial character of which is demonstrated by the position of 
