252 LLOYD’S NATURAL HISTORY. 
Notwithstanding its gigantic stature, it may be inferred from | 
the similarity of the limb-bones of all the fossil Kangaroos to 
those of the living species that this extinct form progressed | 
by leaps in the same manner as its modern cousins. | 
Distribution.— Victoria, Queensland, and New South Wales ; 
the remains occurring beth in the superficial deposits of the | 
two former districts, and likewise in the caverns of the Wel 
lington Valley in the latter. 
GENUS PROCOPTODON. 
Procoptodon, Owen, Phil. Trans., 1874, p. 788. 
The Kangaroos of this genus, although smaller than the pre- 4 
ceding, were likewise, in most cases, of very large size. Agree- | 
ing with the latter in the structure of their premolar teeth, and | 
likewise in the bony union between the two branches of the | 
lower jaw of the adult, they differed by the extreme shortness 
and depth of the whole lower jaw, and the smallness of the in- 
terval between the incisor and premolar teeth. Another pe- 
culiarity is to be found in the circumstance that the enamel of | 
the molar teeth is generally thrown into a number of vertical 
folds and puckerings ; while the lower incisor teeth differ from © 
those of all living Kangaroos in their cylindrical form. The 
skull differs from that of Palorchestes in having unossified 
vacuities in the palate, as in the existing members of the | 
family. The lower jaw is easily recognised by the conversion 
of the usual pit on the outer side of its hinder portion into a 
complete pocket, owing to the g:eat development of its outer 
wall. 
Certain limb-bones which have been tentatively assigned to 
this genus, indicate, if their association with the jaws be 
correct, that the disproportion between the front and hind 
limbs was less marked than is the case in AZacropus. 
